Phorboxazole Compounds and Methods of Their Preparation

ABSTRACT

Novel macrolactone compounds, their methods of preparation, pharmaceutical compositions containing these compounds, and methods for their pharmaceutical use are disclosed. In certain embodiments, the macrolactone compounds may be useful, inter alia, for treating various cancers, inducing apoptosis in malignant cells, or inhibiting cancer cell division.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of Ser. No. 11/408,573, filed on Apr.20, 2006, and also claims priority to U.S. Provisional Application Ser.No. 60/674,004, filed Apr. 21, 2005, the disclosure of each isincorporated herein by reference in its entirety.

GOVERNMENT SUPPORT

Certain of the inventors were supported by National Institutes of HealthGrant CA019033.

FIELD OF THE INVENTION

The invention relates to compounds which mimic the chemical and/orbiological activity of Phorboxazole, compositions containing suchcompounds, and to methods useful in their preparation. Moreparticularly, the present invention relates to novel Phorboxazoleanalogs that may be useful as pharmaceuticals in inducing apoptosis incancer cells.

BACKGROUND OF THE INVENTION

In 1995, Searle and Molinski (J. Am. Chem. Soc. 1995, 117, 8126-8131; J.Am. Chem. Soc. 1996, 118, 9422-9423; Tetrahedron Lett. 1996, 37,7879-7880) isolated (+)-Phorboxazole A (1) and B (2) from a methanolicextract of the sponge Phorbas sp. In vitro bioassay against the NationalCancer Institute's (NCI) panel of 60 human tumor cell lines revealedextraordinary anti-proliferative activity against the entire panel; amean GI₅₀ value of 1.58×10⁻⁹ M for both (+)-Phorboxazole A and B.

While (1) and (2) remain promising anticancer medicinal agents, theirarchitectural complexity warrants exploration of simplified syntheticanalogs. Initial structure activity relationship (SAR) studies conductedby Uckun (WO 01/36048 A1) and Forsyth (Bioorg. Med. Chem. Lett. 2001,11, 1181-1183) disclosed the discovery of two (+)-Phorboxazole Aanalogues which displayed anticancer activity in leukemia, breastcancer, and brain tumor cancer cell lines.

Several groups have been actively involved in devising synthetic routesto Phorboxazole A and/or Phorboxazole B. Forsyth, et al. (J. Am. Chem.Soc. 1998, 120, 5597) have reported a linear synthetic sequence of 100total steps to Phorboxazole A in 0.4% overall yield. Smith, et al., (J.Am. Chem. Soc. 2001, 123, 4834) have prepared Phorboxazole A in anoverall yield of 3%. Pattenden, et al., (Angew. Chem. Int. Ed. 2003, 42,1255) have provided Phorboxazole A in 0.18% overall yield. A 2.4%overall yield of Phorboxazole A was reported by Williams, et al. (Angew.Chem. Int. Ed. 2003, 42, 1258). Evans, et al (Angew. Chem. Int. Ed.2000, 39, 2533, 2536) have developed a route to Phorboxazole B of 71total steps in 12.6% overall yield.

There is therefore a need for improved synthetic methods which providehigh yield and high selectivity, and at a relatively high rate ofreaction, using better, more convenient and/or less expensive processmethodology than many processes known heretofore for the preparation ofPhorboxazole A, Phorboxazole B, their synthetic intermediates, and forcompounds, analogs or derivatives having similar chemical and/orbiological activity. The present invention is directed to these andother important ends.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed in part to novel methodsfor the preparation of Phorboxazole A, Phorboxazole B, and theirsynthetic intermediates. In certain aspects, the invention is directedto new analogs and derivatives of Phorboxazole A and Phorboxazole Bhaving useful chemical and/or biological activity. In other aspects, theinvention is directed to methods of preparation for, compositionscontaining, and methods of use of analogs or derivatives of PhorboxazoleA or Phorboxazole B.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

As employed above and throughout the disclosure, the following terms,unless otherwise indicated, shall be understood to have the followingmeanings.

“Alkyl” refers to an optionally substituted, saturated straight, orbranched, hydrocarbon radical having from about 1 to about 20 carbonatoms (and all combinations and subcombinations of ranges and specificnumbers of carbon atoms therein). Alkyl groups include, but are notlimited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl,t-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, isohexyl,3-methylpentyl, 2,2-dimethylbutyl, and 2,3-dimethylbutyl.

“Alkenyl” refers to an optionally substituted alkyl group having fromabout 2 to about 10 carbon atoms and one or more double bonds (and allcombinations and subcombinations of ranges and specific numbers ofcarbon atoms therein), wherein alkyl is as previously defined.

“Alkynyl” refers to an optionally substituted alkyl group having fromabout 2 to about 10 carbon atoms and one or more triple bonds (and allcombinations and subcombinations of ranges and specific numbers ofcarbon atoms therein), wherein alkyl is as previously defined.

“Aryl” refers to an optionally substituted, mono-, di-, tri-, or othermulticyclic aromatic ring system having from about 5 to about 50 carbonatoms (and all combinations and subcombinations of ranges and specificnumbers of carbon atoms therein), with from about 6 to about 10 carbonsbeing preferred. Non-limiting examples include, for example, phenyl,naphthyl, anthracenyl, and phenanthrenyl.

“Aralkyl” refers to an optionally substituted moiety composed of analkyl radical bearing an aryl substituent and having from about 6 toabout 50 carbon atoms (and all combinations and subcombinations ofranges and specific numbers of carbon atoms therein), with from about 6to about 10 carbon atoms being preferred. Non-limiting examples include,for example, benzyl, diphenylmethyl, triphenylmethyl, phenylethyl, anddiphenylethyl.

“Halo” refers to iodo, bromo, chloro, or fluoro.

Typically, substituted chemical moieties include one or moresubstituents that replace hydrogen. Exemplary substituents include, forexample, halo (e.g., F, Cl, Br, I), alkyl, cycloalkyl, alkylcycloalkyl,alkenyl, alkynyl, aralkyl, aryl, heteroaryl, heteroaralkyl, spiroalkyl,heterocycloalkyl, hydroxyl (—OH), oxo (═O), nitro (—NO₂), cyano (—CN),amino (—NH₂), —N-substituted amino (—NHR″), —N,N-disubstituted amino(—N(R″)R″), carboxy (—COOH), —O—C(═O)R″, —C(═O)R″, —OR″, —C(═O)OR″,—NHC(═O)R″, aminocarbonyl (—C(═O)NH₂), —N-substituted aminocarbonyl(—C(═O)NHR″), —N,N-disubstituted aminocarbonyl (—C(═O)N(R″)R″), thiol,thiolato (—SR″), sulfonic acid (—SO₃H), phosphonic acid (—PO₃H),—P(═O)(OR″)OR″, S(═O)R″, —S(═O)₂R″, —S(═O)₂NH₂, —S(═O)₂ NHR″,—S(═O)₂NR″R″, —NHS(═O)₂R″, —NR″S(═O)₂R″, —CF₃, —CF₂CF₃, —NHC(═O)NHR″,—NHC(═O)NR″R″, —NR″C(═O)NHR″, —NR″C(═O)NR″R″, —NR″C(═O)R″ and the like.In relation to the aforementioned substituents, each moiety R″ can be,independently, any of H, alkyl, cycloalkyl, alkenyl, aryl, aralkyl,heteroaryl, or heterocycloalkyl, or when two R″ groups are attached tothe same nitrogen atom within a substituent, as herein above defined, R″and R″ can be taken together with the nitrogen atom to which they areattached to form a 3- to 8-membered heterocycloalkyl ring, wherein oneor two of the heterocycloalkyl ring carbon atoms independently may beoptionally replaced by —O—, —S—, —SO, —SO₂—, —NH—, —N(alkyl)-,—N(acyl)-, —N(aryl)-, or —N(aroyl)-groups, for example.

When any variable occurs more than one time in any constituent or in anyformula, its definition in each occurrence is independent of itsdefinition at every other occurrence. Combinations of substituentsand/or variables are permissible only if such combinations result instable compounds.

Accordingly, the present invention is directed, in part, to compounds offormula XIX:

wherein:

-   -   R¹ is alkyl, alkenyl, haloalkenyl, alkynyl, or silylated        alkynyl;    -   each R² is independently H, alkyl, aralkyl, aryl, or an hydroxyl        protecting group;    -   each dotted line indicates independently the presence of a        single or double bond; and    -   each Z is H or taken together form an exocyclic methylene        moiety;

provided that when the compound of formula XIX has the structure:

and

R² is H or methyl;

then R¹ is other than:

In certain preferred embodiments the compound of formula XIX has thefollowing structure:

In other preferred embodiments the compound of formula XIX has thefollowing structure:

Preferably, when the compound of formula XIX has the above formula, R¹is:

In certain embodiments, the present invention is directed, in part, tocompounds of formula XXII:

wherein:

-   -   G is —O— or —CH₂—;    -   Q is H or OR², provided that when G is —O—, then Q is H;    -   R¹ is alkyl, alkenyl, haloalkenyl, or alkynyl;    -   each R² is independently H, alkyl, aralkyl, aryl, or an hydroxyl        protecting group;    -   each dotted line indicates independently the presence of a        single or double bond; and    -   each Z is H or taken together form an exocyclic methylene        moiety;

provided that when the compound of formula XXII has the structure:

and

R² is H or methyl;

then R¹ is other than:

In certain embodiments of compounds of the invention, such as forexample, compounds of formula XIX, XX, XXI, XXII, XXIII, and/or XXIV, R¹is alkyl, alkenyl, haloalkenyl, or alkynyl. Alternatively, in certainembodiments, R¹ is more preferably alkyl, alkenyl, or alkynyl. Inembodiments wherein R¹ is alkyl, it is preferably C₁-C₆ alkyl, morepreferably C₁-C₃ alkyl, more preferably C₁-C₂ alkyl, yet more preferablyethyl or methyl. In embodiments wherein R¹ is alkenyl, it is preferablyit is preferably C₂-C₆ alkenyl, more preferably C₂-C₃ alkenyl, morepreferably ethenyl. In embodiments wherein R¹ is haloalkenyl, it ispreferably alkenyl substituted with chloro or bromo, more preferablyC₂-C₃ alkenyl substituted with one chloro or bromo, still morepreferably chloroethenyl or bromoethenyl, with Z-chloroethenyl orZ-bromoethenyl being particularly preferred. In embodiments wherein R¹is alkynyl it is preferably C₂-C₆ alkynyl, more preferably C₂-C₃alkynyl, more preferably ethynyl. In certain preferred embodimentswherein R¹ is alkynyl, it is silylated, more preferably silylatedethynyl, more preferably still tetrabutyldimethylsilylated ethynyl.

Alternatively, R¹ is preferably:

more preferably:

with:

being even more preferred.

In other embodiments of compounds of the invention, such as for examplecompounds of formula XIX, XX, XXI, XXII, XXIII, and/or XXIV, each R² isindependently H, alkyl, aralkyl, aryl, or an hydroxyl protecting group.When R² is alkyl, it is preferably C₁-C₆ alkyl, more preferably C₁-C₃alkyl, more preferably C₁ alkyl, yet more preferably methyl. When R² isaralkyl, it is preferably optionally substituted benzyl; whensubstituted, the phenyl ring of said benzyl is preferably substitutedwith at least one alkoxy, preferably methoxy moiety. When R² is aryl, its preferably phenyl.

The target compounds and intermediates of the present invention maycontain hydroxyl protecting groups. Protecting groups are known per seas chemical functional groups that can be selectively appended to andremoved from functionality present in a chemical compound to render suchfunctionality inert to certain chemical reaction conditions to which thecompound is exposed. When R² an hydroxyl protecting group, it may be anyhydroxyl group utilized by one of ordinary skill in the art. Forexample, see Greene and Wuts, “Protective Groups in Organic Synthesis”,2^(nd) Ed. Wiley and Sons, NY, 1991, the contents of said referenceincorporated herein in its entirety. Numerous hydroxyl protecting groupsare known in the art, including the acid-labile t-butyldimethylsilyl,diethylisopropylsilyl, and triethylsilyl groups and the acid-stablearalkyl (e.g., benzyl), triisopropylsilyl, and t-butyldiphenylsilylgroups. Preferably, the protecting group is a silyl protecting group,such as for example, tertbutyldimethylsilyl, triisopropylsilyl,tertbuylbisphenylsilyl, and the like.

In certain preferred embodiments the compound of formula XXII has thefollowing structure:

In other preferred embodiments, the compound of formula XXII has thefollowing structure:

In other embodiments, the invention is directed to processes forpreparing a compound of formula XIX:

wherein:

-   -   R¹ is alkyl, alkenyl, haloalkenyl, or alkynyl;    -   each R² is independently H, alkyl, aralkyl, aryl, or an hydroxyl        protecting group;    -   each dotted line indicates independently the presence of a        single or double bond; and    -   each Z is H or taken together form an exocyclic methylene        moiety,

comprising the steps of:

-   -   contacting a compound of formula XX:

-   -   with a compound of formula XXI:

wherein:

-   -   R¹ is alkyl, alkenyl, haloalkenyl, or alkynyl; and    -   each R² is independently H, alkyl, aralkyl, aryl, or hydroxyl        protecting group;

for a time and under conditions effective to provide a compound offormula XIX.

In other embodiments, the invention is directed to processes forpreparing a compound of formula XIX:

wherein:

-   -   each R² is independently H, alkyl, aralkyl, aryl, or an hydroxyl        protecting group; and    -   each Z is H or taken together form an exocyclic methylene        moiety,

comprising the steps of:

contacting a compound of formula:

with a compound of formula:

a lactonization agent, and a base

for a time and under conditions effective to provide a compound offormula XX.

In other embodiments, the invention is directed to processes forpreparing a compound of formula XXII:

wherein:

-   -   G is —O— or —CH₂—;    -   Q is H or OR², provided that when G is —O—, then Q is H;    -   R¹ is alkyl, alkenyl, haloalkenyl, or alkynyl;    -   each R² is independently H, alkyl, aralkyl, aryl, or an hydroxyl        protecting group;    -   each dotted line indicates independently the presence of a        single or double bond; and    -   each Z is H or taken together form an exocyclic methylene        moiety,

comprising the steps of:

-   -   contacting a compound of formula XXIII:

with a compound of formula XXIV:

wherein:

-   -   R¹ is alkyl, alkenyl, haloalkenyl, or alkynyl; and    -   each R² is independently H, alkyl, aralkyl, aryl, or hydroxyl        protecting group;

for a time and under conditions effective to provide a compound offormula XXII.

The present invention is also directed, in part, to processes forpreparing a compound of formula XXIII:

-   -   wherein:    -   each R² is independently H, alkyl, aralkyl, aryl, or an hydroxyl        protecting group; and    -   each Z is H or taken together form an exocyclic methylene        moiety,

comprising the steps of:

contacting a compound of formula:

with a compound of formula:

a lactonization agent, and a base

for a time and under conditions effective to provide a compound offormula XXIII.

Although the compounds of the present invention may be administered asthe pure chemicals, it is preferable to present the active ingredient asa pharmaceutical composition. The invention thus further provides apharmaceutical composition comprising one or more of the cannabinoidreceptor modulator compounds of the present invention, together with oneor more pharmaceutically acceptable carriers therefore and, optionally,other therapeutic and/or prophylactic ingredients. The carrier(s) mustbe acceptable in the sense of being compatible with the otheringredients of the composition and not deleterious to the recipientthereof.

The compounds of formula XIX and/or XXII are preferably combined with apharmaceutical carrier selected on the basis of the chosen route ofadministration and standard pharmaceutical practice as described, forexample, in Remington's Pharmaceutical Sciences (Mack Pub. Co., Easton,Pa., 1980), the disclosure of which is hereby incorporated herein byreference, in its entirety.

In other preferred embodiments, the invention is directed, in part, tomethods of inducing apoptosis in malignant cells, comprising the step ofcontacting said cells with an effective amount of a compound of theinvention, such as, for example a compound of formula formula XIX, XX,XXI, XXII, XXIII, and/or XXIV. In certain more preferred embodiments,apoptosis occurs in vitro. In other more preferred embodiments,apoptosis occurs in vivo.

Among preferable embodiments included herein, the invention is directed,in part, to methods for inhibiting cancer cell division, comprising thestep of contacting said cells with an effective amount of a compound ofthe invention.

In certain preferred embodiments, the invention is directed, in part, tomethods for treating cancer in a patient in need thereof, comprising thestep of administering to said patient an effective amount of a compoundof the invention, such as for example, a compound of formula XIX, XX,XXI, XXII, XXIII, and/or XXIV; preferably wherein the cancer treated isselected from the group consisting of pancreatic, breast, centralnervous system, non-small lung, colon, and prostate cancers.

Methods of Preparation

The previously disclosed compound I (Smith, et al., J. Am. Chem. Soc.2001, 123, 10942) was provided (Scheme I) by the application of aspectsof methodology of Keck, et al. (J. Org. Chem. 1995, 60, 5998) andYamashita, et al. (J. Am. Chem. Soc. 2003, 125, 3793) from knownaldehyde 2.100 of Boeckman, et al. (J. Am. Chem. Soc. 1987, 109, 7553).

Compound I was transformed into II (Scheme II) by the application ofaspects of methodology of Nagao, et al., J. Chem. Soc. Com. 1985, 1418,Petasis, et al., Tetrahedron Lett. 1996, 2279, and Smith, et al., Org.Lett. 1999, 1, 909. The oxazolyl aldehyde 3.48 utilized in the secondreaction step (Scheme II) and tetrahydropyranone II were previouslydisclosed in Smith, et al. (J. Am. Chem. Soc. 2001, 123, 10942-53).

II was selectively reduced to the corresponding axial alcohol (−)-2.104using K-Selectride (this isomer was utilized in the preparation ofPhorboxazole A and all analogs with similar stereochemistry at thiscenter) followed by protection of the secondary alcohol withtert-butyldimethylsilyl triflate. PMB Deprotection with DDQ followed bymesylation gave III [(−)-2.51] in 29% overall yield. Alternatively, theequatorial alcohol may be provided by reducing II with, for examplesodium borohydride, by inference of borohydride reductions on similarsubstrates. Utilization of the equatorial alcohol, upon completion ofthe remaining steps described in Scheme III, would then provide theisomer used in the preparation of Phorboxazole B.

Intermediate IV [(+)-2.44] was prepared in 35% overall yield (Scheme IV)applying aspects of the chemistry of Evans, et al. (J. Am. Chem. Soc.1981, 103, 2127) from known β-hydroxy carboxylic acid (+)-2.21 of Smith,et al. (Org. Lett. 1999, 1, 913). (In Scheme IV, the followingabbreviations have these meanings: Bu₂BOTf is dibutylboron triflate,HMDS is hexamethyldisilazide, 2,6-DTBMP is2,6-di-tert-butyl-4-methylpyridine, DMBCl is 3,4-dimethoxybenzylchloride, and BORSM is based on recovered starting material.)

The chemistry of Liu, et al. (J. Am. Chem. Soc. 2000, 122, 1235) andEvans, et al. (J. Am. Chem. Soc. 2000, 122, 10033) was effectivelyapplied for the preparation of VI [(+)-2.46] from III [(−)-2.52] and IV[(+)-2.44]. Removal of the silyl protecting group of IV with subsequentDess-Martin oxidation of the primary alcohol gave aldehyde V [(+)-2.12]in 94% yield. V was then converted via Wittig olefination with thephosphonium salt derived from III [(−)-2.52] in DMF to provide VI[(+)-2.46] with 20:1 E/Z selectivity in 94% yield, as shown in Scheme V.

The silylated primary alcohol VI [(+)-2.46] was deprotected with KOH andthen oxidized using Dess-Martin chemistry to give, after DMB removalwith DDQ, the aldehyde of formula VII [(+)-2.10]. Phosphonate typeWittig reaction of VII [(+)-2.10] entailed coupling with the phosphonatecarboxylic acid 3.45, and olefination to provide VIII [(+)-2.5] in 18%overall yield. The E and Z isomers of VIII [(+)-2.5] were separableusing medium pressure column chromatography using silica gel (SchemeVI).

IX was reacted with a TMS protected acetylenyl stannane under conditionsearlier disclosed in Smith, et al. (Synlett. 2001, 1543, and in J. Am.Chem. Soc. 2001, 123, 10942-53) and further converted to X [(−)-2.S₅]. X[(−)-2.S₅] was stannylated with hexamethylditin in the presence of apalladium catalyst to give XI [(−)-2.90]. TIPS stands for the silylprotecting group triisopropylsilyl in the schemes herein (Scheme VII).

Analogous to the chemistry used to prepare XI [(−)-2.90], compound IXwas reacted with vinyl stannane IXa [3.24] (Scheme IX) to provide anintermediate which upon further transformation yielded XII [(−)-3.20](Scheme VIII).

Deprotection of the acetylene of X [(−)-2.S₅] (from Scheme VII) withsilver nitrate to XIII [(−)-3.28] followed by partial hydrogenation gavean intermediate triflate which was stannylated with hexamethylditin inthe presence of a palladium catalyst to give XIV [(−)-3.19] (Scheme X).In the partial hydrogenation step, 1-hexene was used as a hydrogenscavenger to protect against over-reduction of the intermediate triflate

The terminal acetylene of Intermediate XIII [(−)-3.28] wasE-hydrostannylated with AIBN and tributyltin hydride, which upontreatment with CuCl₂, followed by stannylation of the triflate gave XV[(−)-3.21] (Scheme XI). Alternatively, after treatment with CuCl₂, thetriflate may be treated with a tetraalkoxydiborane, such as for example,[2,2′]Bi[[1,3,2]dioxaborolanyl] or the like in the presence of apalladium catalyst to provide the corresponding borane analog of XV[(−)-3.21]. The carbon atoms of the diborane reagent may each besubstituted with an alkyl or aryl substituent.

Stille coupling of VIII [(+)-2.5Z or (+)-2.5E] with XI [(−)-2.90], XII[(−)-3.20], XIV [(−)-3.19], or XV [(−)-3.21] or a borane analog thereofusing a palladium catalyst, triphenylarsine, diphenylphosphonate saltand diisopropylethylamine in DMF gave the corresponding XVIa, [(+)-3.35and (+)-3.39] XVIb [(+)-3.37], XVIc [(+)-3.36], XVId [(+)-3.38] or XVIe[(+)-3.40], respectively (Scheme XII).

SCHEME XII

C45-C-46 Sidechain R = Yield a)

(+)-3.35 Z-Macrocyle: 68% (+)-3.39 E-Macrocycle: 66% b)

(+)-3.37 Z-Macrocycle: 82% c) e)

(+)-3.36 Z-Marcrocycle: 77% (+)-3.40 Central Pyran: 69% d)

(+)-3.38 Z-Macrocycle: 87%

Final elaboration of (+)-Phorboxazole A was carried by reacting XVIa[(+)-3.35] with silver nitrate to provide the bromo acetylene (+)-2.92.A palladium mediated hydrostannylation with tributyltin hydride,followed by treatment of the stannane with N-bromosuccinimide,subsequent desilylation of the secondary alcohols and deprotection ofthe lactol with aqueous hydrochloric acid to give the desired(+)-Phorboxazole A XVIII [(+)-1] (Scheme XIII).

The secondary alcohols in analogs XVI(a-e) were desilylated usingtetrabutylammonium fluoride in THF. Deprotection of the of the lactolwith aqueous hydrochloric acid gave the desired products XVII(a-e). Thecentral pyran XVIIe [(−)-3.41] noted in Scheme XIV and below wasprepared by coupling IV [(+)-2.44] with XIV [(−)-3.19] using conditionsgenerally described in Scheme XII.

SCHEME XIV

C45-C46 Sidechain R = Yield a)

Z-Macrocycle: 64% XVIIaZ [(+)-3.11] E-Macrocycle: 69% XVIIaE [(+)-3.15]b)

Z-Macrocycle: 86% XVIIb [(−)-3.13] c) e)

Z-Macrocyle: 67% XVIIc [(+)-3.12] Central Pyran: 66% XVIIe [(−)-3.41] d)

Z-Macrocycle: 61% XVIId [(+)-3.14]

The synthesis of E and Z macrocycles (3.43Z and 3.43E) began withconstruction of the Wittig salt of 3.52 (Scheme XV). β-Hydroxy thioimide(−)-3.50, prepared by treatment of I (see Scheme II) with1-(4-Isopropyl-2-thioxo-thiazolidin-3-yl)-ethanone in the presence oftin(II) triflate and ethyl piperidine (see Nagao, et al., J. Chem. Soc.Com. 1985, 1418, and Smith, et al, Org. Lett. 1999, 1, 909) was reducedto diol (−)-3.49 employing lithium borohydride (LiBH₄). Under Noyoricondensation conditions, treatment of diol (−)-3.49 with HMDS affordedthe corresponding bis-silylated diol (Noyori, R. et al., Tetrahedron,1981, 37, 3899). When condensed with oxazole aldehyde 3.48, promoted byTMSOTF, acetal (−)-3.51 was produced as a mixture in 86% yield (ca. 7:1,cis:trans). After separation, exposure of (−)-3.51 to wet DDQ gave riseto the primary alcohol that, when treated with MsCl and DIPEA, affordedmesylate (−)-3.52 in 82% yield over the two steps. Construction of theC(19-20) E-olefin next called upon the productive one-flask Wittig saltformation/olefination protocol of Evans, et al. (J. Am. Chem. Soc. 2000,122, 10033). To this end, treatment of mesylate (−)-3.52 with PBu₃,followed by aldehyde V [(+)-2.12] and DBU furnished tetracycle (+)-3.53in 91% yield with excellent configurational control (ca. 19:1, E:Z).

Completion of both the E and Z-macrocycles (3.43Z and 3.43E) continuedwith removal of the BPS protecting group with TBAF, followed byoxidation of the resultant primary alcohol with the Dess-Martinperiodinane to furnish aldehyde (+)-3.54 in good yield. Exposure to DDQpromoted the removal of the 3,4-dimethoxylbenzyl (DMB) protecting groupto furnish aldehyde-alcohol (+)-3.44 in an excellent 98% yield (SchemeXVI). While problematic in the

second generation synthesis of (+)-phorboxazole A, application of theStill modified Horner-Emmons olefination, Still, et al. (TetrahedronLett. 1983, 24, 4405), in the C(11-15) acetal series wouldadvantageously provide access to both the Z and E-C(2-3) macrocycles. Tothis end, EDCI.MeI/HOBT promoted union of aldehyde-alcohol (+)-3.44 withphosphonate acid 3.45 gave rise to the corresponding phosphonate esterin 82% yield. Treatment with K₂CO₃ and 18-crown-6 promoted theintramolecular Still-Gennari olefination to provide Z and E-macrocycles(+)-3.43Z and (+)-3.43E respectively, in 88% combined yield, as areadily separable mixture (ca. 2.1:1, Z:E, only Z-isomer shown).

Addition of the Grignard reagent derived from oxazole 2.9 to dienyllactone (−)-2.80 (derived from vinyl iodide IX in Scheme VII) gave riseto the C(33) hemiacetal (Scheme XVII). Immediate treatment withtriethylsilyl trifluoromethanesulfonate (TESOTf) and 2,6-lutidineprovided the C(33) TES protected hemiacetal (−)-3.56 in modest yield.Employing Pd(PPh₃)₄ and (Me₃Sn)₂, conversion to the fully elaboratedtrimethylstannane (−)-3.57 proceeded in 55% yield. This yield issignificantly lower than observed in our (+)-phorboxazole A and C(45-46)analogue syntheses, presumably due to decomposition of the TEShemiacetal under the harsh reaction conditions.

Continuing with the syntheses of 3.42Z and 3.42E, union of Z andE-acetal macrocycles (+)-3.43Z and (+)-3.43E with oxazole stannane(−)-3.57 under the phorboxazole Stille coupling protocol smoothlyfurnished the corresponding Z and E-coupled products (Scheme XVIII).Final treatment with 4 equivalents of TBAF promoted global removal ofthe C(46) TMS, C(38) TIPS and C(33) TES protecting groups to furnishC(11-15) acetal analogues XVIIfZ [(+)-3.42Z] and XVIIfE [(+)-3.42E] in54% and 49% yield respectively (only Z-isomer shown, Smith, A. B., etal., (Org. Lett. 2006, 8, 797).

Experimental Procedures

Unless otherwise noted, all solvents were reagent grade. Diethyl ether(Et₂O) and tetrahydrofuran (THF) were freshly distilled fromsodium/benzophenone under argon. N-Butyllithium and t-butyllithium werepurchased from Aldrich. Reactions were magnetically stirred andmonitored by thin layer chromatography (TLC) with 0.25 mm E. Merckpre-coated silica gel plates. Flash chromatography was performed withsilica gel 60 (particle size 0.040-0.062 mm) supplied by Silicycle andSorbent Technologies. Yields refer to chromatographically andspectroscopically pure compounds, unless otherwise stated. Infraredspectra were recorded on a JASCO-Model FT/IR-480 Plus spectrometer.Proton and carbon-13 NMR spectra were recorded on a BRUKER-AMX-500spectrometer. Chemical shifts are reported relative to either chloroform(d 7.26) or benzene (d 7.15) for ¹H-NMR and either chloroform (d 77.0)or benzene (d 128.0) for ¹³C NMR. Optical rotations were measured on aPERKIN-ELMER-model 241 polarimeter. High resolution mass spectra weremeasured at the University of Pennsylvania Mass Spectrometry ServiceCenter.

Trans-Tetrahydropyranone Thiolester (−)-2.25:

To a solution of known enone (−)-2.23 (Smith, et al. J. Am. Chem. Soc.2001, 123, 10942) (6.93 g, 18.2 mmol) and scandium triflate [Sc(OTf)₃](89.3 mg, 0.182 mmol) in dichloromethane (91.2 mL) under argon was addeddropwise, the TMS-enol ether derived from ethylthioacetate (4.83 g, 27.4mmol) at −78° C. The reaction mixture was stirred for 15 minutes at −78°C. and then quenched via dropwise addition of methanol/pyridine (1:1,100 mL) and warmed to room temperature. After one hour and thirtyminutes the layers of the biphasic mixture were separated and theaqueous layer was extracted with dichloromethane (70 mL, 3×). Thecombined organic layers were dried over Na₂SO₄, filtered andconcentrated under reduced pressure. Purification via silica gelchromatography (10% EtOAc/hexanes) afforded trans-tetrahydropyranonethiolester (−)-2.25 (8.39 g, 95%) as a light yellow oil: [α]_(D) ²⁰-9.1(c 2.3, CHCl₃); IR (CHCl₃) 2931 (m), 2857 (m), 1719 (s), 1685 (s), 1472(w), 1428 (m), 1112 (s), 998 (w), 823 (w), 739 (m), 614 (m) cm⁻¹; ¹HNMR(500 MHz, CDCl₃) δ 7.65 (m, 4H), 7.38 (m, 6H), 4.50 (m, 1H), 4.41 (ddd,J=8.6, 5.7, 5.5 Hz, 1H), 3.79 (ddd, J=10.5, 7.8, 5.4 Hz, 1H), 3.71 (m,1H), 2.84 (m, 3H), 2.65 (dd, J=14.9, 5.8 Hz, 1H), 2.58 (ddd, J=14.5,5.3, 1.1 Hz, 1H), 2.53 (ddd, J=14.5, 4.7, 1.3 Hz, 1H), 2.33 (ddd,J=14.7, 7.6, 1.1 Hz, 1H), 2.30 (ddd, J=14.5, 6.2, 1.3 Hz, 1H), 1.89 (m,1H), 1.68 (m, 1H), 1.20 (app t, J=7.4 Hz, 3H), 1.05 (s, 9H); ¹³CNMR (125MHz, CDCl₃) δ 206.2, 195.7, 135.5, 133.7, 133.6, 129.6, 129.5, 127.7,70.0, 68.7, 59.9, 48.7, 46.5, 46.2, 36.7, 26.9, 23.5, 19.2, 14.5; highresolution mass spectrum (ES⁺) m/z 507.2024 [(M+Na)⁺; calcd. forC₂₇H₃₆O₄SSiNa: 507.2001].

Trans-Tetrahydropyran exo-Olefin (−)-2.26:

To a solution of thiolester (−)-2.25 (8.39 g, 17.3 mmol) and ethylpivalate (0.503 mL, 3.11 mmol) in THF (14.7 mL) under argon at roomtemperature was added dimethyltitanocene (0.5 M/THF) (62.3 mL, 31.1mmol) followed by heating to 55° C. with the exclusion of light. Aftertwenty hours, the reaction mixture was cooled to room temperature,diluted with hexanes (6 mL) and filtered through a pad of Celite. Theresultant filtrate was then concentrated under reduced pressure. Thecrude product was dissolved in chloroform (15 mL), washed with 1Nhydrogen chloride solution (15 mL, 1×), dried over Na₂SO₄, filtered andconcentrated under reduced pressure. Purification via silica gelchromatography (2.5% EtOAc/hexanes) afforded trans-tetrahydropyranexo-olefin (−)-2.26 (6.35 g, 79%) as a light yellow oil: [α]_(D) ²⁰−21.2(c 1.1, CHCl₃); IR(CHCl₃) 3071 (m), 2931 (s), 1689 (s), 1685 (s), 1473(w), 1428 (s), 1265 (w), 1112 (s), 998 (m), 894 (w), 823 (w), 739 (m),702 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.66 (m, 4H), 7.40 (m, 6H), 4.79(s, 2H), 4.24 (m, 1H), 4.01 (m, 1H), 3.75 (m, 1H), 3.72 (m, 1H), 2.82(m, 2H), 2.80 (dd, J=14.5, 7.2 Hz, 1H), 2.65 (dd, J=14.5, 6.4 Hz, 1H),2.36 (m, 2H), 2.05 (dd, J=13.2, 6.1 Hz, 1H), 1.99 (dd, J=13.2, 6.5 Hz,1H), 1.88 (m, 1H), 1.65 (m, 1H), 1.20 (app t, J=7.4 Hz, 3H), 1.05 (s,9H); ¹³CNMR (125 MHz, CDCl₃) δ 196.8, 141.3, 135.5, 134.0, 133.9, 129.5,129.4, 127.6, 111.0, 69.7, 69.3, 60.6, 47.8, 39.5, 39.1, 36.3, 26.9,23.3, 19.2, 14.6; high resolution mass spectrum (ES⁺) m/z 505.2229[(M+Na)⁺; calcd for C₂₉H₃₈O₃SSiNa: 505.2209].

Dioxanone (+)-2.42:

Under argon, a solution of known β-hydroxy acid (+)-2.21 (Smith, et al.Org. Lett. 1999, 1, 913) (14.5 g, 37.6 mmol) in dichloromethane (114 mL)was treated with 1,1,1,3,3,3-hexamethyldisilazane (8.72 mL) at roomtemperature. After stirring twenty-four hours, the reaction wasconcentrated under reduced pressure followed by drying under vacuum (toremove excess 1,1,1,3,3,3-hexamethyldisilazane) to provide thecorresponding bis-silylated β-hydroxy acid that was used without anyfurther purification. Under argon, a solution of the bis-silylatedβ-hydroxy acid, 2,6-di-tert-butyl-4-methylpyridine (2,6-DTBMP) (386 mg,1.88 mmol) and known freshly prepared E-C(2-3)-iodomethacrolein 2.20(Ahmed, et al. Tetrahedron Lett. 1998, 39, 183) (9.94 g, 50.7 mmol) indichloromethane (150 mL) at −78° C. was treated withtrimethylsilyltrifluoromethylsulfonate (TMSOTf) (1.50 mL, 8.26 mmol).After 30 min, trifluoromethanesulfonic acid (TfOH) (300 mL, 3.38 mmol)was added dropwise and the reaction mixture stirred at −78° C. After twohours, the reaction was quenched via dropwise addition of pyridine (1.16mL), warmed to room temperature and concentrated under reduced pressure.Purification via silylated silica gel chromatography (50% EtOAc/hexanes)afforded dioxanone (+)-2.42 (19.7 g, 93%, 20:1 dr) as a light yellowoil: [α]_(D) ²⁰+5.7 (c 1.4, CHCl₃); IR (CHCl₃) 2931 (m), 2857 (m), 1700(s), 1472 (w), 1428 (m), 1112 (s), 822 (w) cm⁻¹; ¹HNMR (500 MHz, CDCl₃)δ 7.62 (m, 4H), 7.39 (m, 6H), 6.63 (s, 1H), 5.53 (s, 1H), 4.28 (ddd,J=8.1, 4.3, 4.3 Hz, 1H), 3.78 (m, 2H), 2.70 (ddd, J=16.7, 9.3, 5.3 Hz,1H), 1.83 (d, J=1.0 Hz, 3H), 1.72 (m, 2H), 1.23 (d, J=7.3 Hz, 3H), 1.04(s, 9H); ¹³CNMR (125 MHz, CDCl₃) δ 171.4, 142.5, 135.5, 133.4, 133.3,129.8, 129.7 127.8, 102.3, 85.3, 73.4, 59.3, 39.4, 33.9, 26.8, 19.2,18.7, 12.1; high resolution mass spectrum (ES⁺) m/z 587.1093 [(M+Na)⁺;calcd for C₂₆H₃₃O₄SiINa: 587.1091].

Enol Acetal (+)-2.19:

Under argon, a solution of dioxanone (+)-2.42 (7.58 g, 13.4 mmol) wastreated with dimethyltitanocene (0.5 M/THF) (80.6 mL, 40.3 mmol), andthe resultant solution was stirred at 55° C. in the absence of light.After twenty three hours, the reaction mixture was cooled to roomtemperature and diluted with hexanes (200 mL). The resultant yellowprecipitate was filtered through a pad of Celite, and the filtrate wasconcentrated under reduced pressure. Flash chromatography on silylatedsilica gel (7% EtOAc/hexanes) furnished enol acetal (+)-2.19 (5.98 g,79%) as a colorless oil: [α]_(D) ²⁰+29.8 (c 2.3, CHCl₃); IR (CHCl₃) 2930(m), 2857 (m), 1653 (w), 1472 (w), 1428 (m), 1289 (w), 1259 (m), 1112(s), 997 (m), 823 (w), 738 (m), 701 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ7.66 (m, 4H), 7.40 (m, 6H), 6.59 (d, J=0.7 Hz, 1H), 4.97 (s, 1H), 4.45(s, 1H), 4.24 (s, 1H), 4.06 (m, 1H), 3.80 (ddd, J=10.2, 10.2, 4.8 Hz,1H), 3.74 (ddd, J=10.2, 5.3, 5.0 Hz, 1H), 2.25 (dddd, J=13.9, 7.0, 7.0,2.5 Hz, 1H), 1.90 (d, J=0.9 Hz, 3H), 1.81 (m, 1H), 1.68 (m, 1H), 1.15(d, J=7.0 Hz, 3H), 1.06 (s, 9H); ¹³CNMR (125 MHz, CDCl₃) δ 162.2, 144.3,135.5, 133.7, 133.6, 129.7, 129.6, 127.7, 102.6, 92.6, 83.6, 75.7, 59.8,36.9, 34.9, 26.9, 19.2, 19.1, 13.5; high resolution mass spectrum (ES)m/z 585.1324 [(M+Na)⁺; calcd for C₂₇H₃₅O₃SiINa: 585.1298].

Tetrahydropyran (+)-2.43:

Under argon, a solution of enol acetal (+)-2.19 (5.27 g, 9.38 mmol) indichloromethane (94 mL) was treated dropwise with Me₂AlCl (1.0 M/hexane)(11.25 mL, 11.25 mmol) at −78° C. After stirring for five minutes, thereaction mixture was warmed to 0° C. and stirred for three minutes. Thereaction was then re-cooled to −78° C. and quenched with triethylamine(4.5 mL), followed by treatment with saturated aqueous sodiumbicarbonate (70 mL) and warmed to room temperature with stirring. Theresulting mixture was diluted with dichloromethane (150 mL) and 1Nhydrogen chloride solution (70 mL) and the layers separated. The aqueouslayer was extracted with dichloromethane (200 mL, 2×) and the combinedorganic extracts were dried over Na₂SO₄, filtered and concentrated underreduced pressure. Purification via silica gel chromatography (5%EtOAc/hexanes) provided tetrahydropyran (+)-2.43 (5.26 g, 99%) as acolorless oil: [α]_(D) ²⁰+66.4 (c 1.2, CHCl₃); IR (CHCl₃) 2929 (m), 2856(m), 1719 (s), 1472 (w), 1428 (m), 1112 (s), 822 (w), 738 (m), 702 (s)cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.64 (m, 4H), 7.40 (m, 6H), 6.36 (dd,J=1.1, 1.0 Hz, 1H), 4.00 (dd, J=11.8, 2.4 Hz, 1H), 3.93 (ddd, J=9.1,3.3, 2.7 Hz, 1H), 3.82 (ddd, J=10.2, 9.1, 4.7 Hz, 1H), 3.75 (ddd,J=10.2, 5.9, 4.4 Hz, 1H), 2.51 (dd, J=14.5, 11.8 Hz, 1H), 2.36 (m, 1H),2.34 (ddd, J=14.5, 2.9, 1.2 Hz, 1H), 1.88 (m, 1H), 1.83 (d, J=0.9 Hz,3H), 1.65 (m, 1H), 1.12 (d, J=7.2 Hz, 3H), 1.03 (s, 9H); ¹³CNMR (125MHz, CDCl₃) δ 210.4, 146.0, 135.5, 133.7, 133.6, 129.7, 129.6, 127.7,80.2, 79.2, 75.2, 60.0, 49.0, 42.7, 34.6, 26.8, 20.6, 19.2, 10.9; highresolution mass spectrum (ES⁺) m/z 585.1291 [(M+Na)⁺; calcd forC₂₇H₃₅O₃SiINa: 585.1298].

Methylated Tetrahydropyranone (+)-2.18:

Under argon, lithium hexamethyldisilazane (LiHMDS) (1.19 M/THF) (9.92mL, 11.8 mmol) was diluted with THF (9.92 mL) at room temperature andcooled to −78° C. A solution of tetrahydropyranone (+)-2.43 (6.03 g,10.7 mmol) in THF (53.5 mL) was added dropwise via cannula to thediluted lithium hexamethyldisilazane solution under stirring. Afterstirring for thirty minutes at −78° C., the solution was warmed to −20°C. and stirred for one hour. A cooled solution (−20° C.) of methyliodide (2.00 mL, 32.2 mmol) and HMPA (5.60 mL, 32.2 mmol) in THF (21.5mL) was added dropwise via cannula and the reaction mixture was stirredat −20° C. After two hours, the reaction was quenched with saturatedaqueous ammonium chloride (130 mL), warmed to room temperature, stirredfor thirty minutes and then extracted with diethyl ether (150 mL, 3×).The combined organic extracts were washed with saturated aqueousammonium chloride (200 mL) and saturated aqueous sodium chloride (200mL), dried over Na₂SO₄, filtered and concentrated under reducedpressure. Purification via silica gel chromatography (2.5%EtOAc/hexanes) furnished methylated tetrahydropyranone (+)-2.18 (4.20 g,68%; 91% based on recovered starting material), as a colorless oil andstarting material (+)-2.43 (1.53 g, 25%); [α]_(D) ²⁰+12.6 (c 1.1,CHCl₃); IR (CHCl₃) 2930 (m), 2857 (m), 1715 (s), 1457 (w), 1428 (m),1282 (w), 1197 (w), 1112 (s), 822 (w), 738 (m), 701 (s) cm⁻¹; ¹HNMR (500MHz, CDCl₃) δ 7.64 (m, 4H), 7.40 (m, 6H), 6.25 (d, J=0.6 Hz, 1H), 3.93(ddd, J=8.8, 4.0, 2.4 Hz, 1H), 3.77 (ddd, J=10.0, 10.0, 4.7 Hz, 1H),3.70 (ddd, J=10.0, 4.9, 4.9 Hz, 1H), 3.66 (d, J=10.5 Hz, 1H), 2.65(dddd, J=14.4, 10.5, 6.6, 3.9 Hz, 1H), 2.43 (dddd, J=11.8, 7.1, 4.7, 2.4Hz, 1H), 1.90 (d, J=0.5 Hz, 3H), 1.85 (m, 1H), 1.64 (m, 1H), 1.15 (d,J=7.1 Hz, 3H), 1.04 (s, 9H), 0.86 (d, J=6.6 Hz, 3H); ¹³CNMR (125 MHz,CDCl₃) δ 211.8, 145.5, 135.5, 133.7, 133.6, 129.6, 129.4, 127.7, 88.0,81.7, 75.7, 60.0, 49.3, 43.2, 34.6, 26.8, 19.2, 18.8, 11.2, 9.3; highresolution mass spectrum (ES⁺) m/z 599.1467 [(M+Na)⁺; calcd forC₂₈H₃₇O₃SiINa: 599.1454].

Secondary Alcohol (+)-2.S₁:

To a solution of methylated tetrahydropyranone (+)-2.18 (5.88 g, 10.2mmol) in ethanol (51 mL) at −10° C. under argon was added sodiumborohydride (772 mg, 20.4 mmol) in one portion. After stirring forthirty minutes, the reaction mixture was treated with saturated aqueousammonium chloride (80 mL) followed by dilution with chloroform (100 mL).The resulting layers were separated, and the aqueous layer was extractedwith chloroform (100 mL, 2×). The combined organic extracts were driedover Na₂SO₄, filtered and concentrated under reduced pressure.Purification via silica gel chromatography (10% EtOAc/hexanes→20%EtOAc/hexanes) afforded secondary alcohol (+)-2.S₁ (4.80 g, 81%, 6.8:1dr) as a colorless oil and the secondary alcohol epimer (−)-2.S₂ (0.68g, 12%). (+)-2.S₁: [α]_(D) ²⁰+15.9 (c 1.2, CHCl₃); IR (CHCl₃) 3446 (b),2959 (m), 2929 (m), 2857 (m), 1471 (w), 1428 (m), 1389 (w), 1279 (w),1112 (s), 1088 (s), 1053 (m), 822 (w), 737 (m), 701 (s) cm⁻¹; ¹HNMR (500MHz, CDCl₃) δ 7.65 (m, 4H), 7.40 (m, 6H), 6.19 (d, J=0.6 Hz, 1H), 3.77(ddd, J=10.1, 8.3, 5.0 Hz, 1H), 3.69 (ddd, J=10.1, 5.5, 5.0 Hz, 1H),3.67 (m, 1H), 3.44 (d, J=10.3 Hz, 1H), 3.43 (d, J=10.1 Hz, 1H), 1.82 (m,2H), 1.81 (d, J=1.0 Hz, 3H), 1.64 (m, 2H), 1.05 (s, 9H), 0.90 (d, J=6.9Hz, 3H), 0.81 (d, J=6.5 Hz, 3H); ¹³CNMR (125 MHz, CDCl₃) δ 146.5, 135.5,133.9, 133.8, 129.7, 129.6, 127.6, 87.2, 80.6, 76.7, 75.0, 60.4, 38.4,35.5, 34.7, 26.9, 19.3, 19.2, 13.2, 5.7; high resolution mass spectrum(ES⁺) m/z 601.1626 [(M+Na)⁺; calcd for C₂₈H₃₉O₃SiINa: 601.1611].

(−)-2.S₂; a light yellow oil; [α]_(D) ²⁰−2.4 (c 1.8, CHCl₃); IR (CHCl₃)3474 (b), 3070 (w), 2960 (s), 2930 (s), 2857 (s), 1617 (w), 1589 (w),1473 (m), 1428 (s), 1390 (m), 1278 (m), 1112 (s), 982 (m), 823 (m), 738(m), 701 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.67 (m, 4H), 7.38 (m, 6H),6.19 (d, J=0.7 Hz, 1H), 4.12 (m, 1H), 3.94 (d, J=10.6 Hz, 1H), 3.73 (m,3H), 1.81 (d, J=1.0 Hz, 3H), 1.80 (m, 2H), 1.62 (m, 2H), 1.46 (br s,1H), 1.06 (s, 9H), 0.93 (d, J=7.1 Hz, 3H), 0.76 (d, J=7.0 Hz, 3H);¹³CNMR (125 MHz, CDCl₃) δ 147.1, 135.6, 134.0, 133.9, 129.5, 129.4,127.6, 82.8, 80.2, 75.0, 70.0, 60.7, 39.3, 35.4, 32.0, 26.9, 19.3, 19.2,13.3, 10.9; high resolution mass spectrum (ES⁺) m/z 601.1617 [(M+Na)⁺;calcd for C₂₈H₃₉O₃SiINa: 601.1611].

DMB Ether (+)-2.44:

To a solution of the alcohol (+)-2.S₁ (3.04 g, 5.26 mmol) in THF (52 mL)at 0° C. under argon was added 18-crown-6 (316 mL, 1.58 mmol), 35%potassium hydride (1.21 g, 10.5 mmol) and 3,4-dimethoxybenzyl chloride(1.47 g, 7.89 mmol) followed by warming to 65° C. After ten minutes, thereaction mixture was cooled to 0° C. and quenched with saturated aqueousammonium chloride (70 mL). The resultant mixture was extracted withchloroform (100 mL, 3×) and the combined organic extracts were driedover Na₂SO₄, filtered and concentrated under reduced pressure.Purification via silica gel chromatography (50% CHCl₃/hexanes→100%CHCl₃) afforded a mixture of the desired DMB ether (+)-2.44 and3,4-dimethoxybenzyl alcohol. A second silica gel flash chromatography(10% EtOAc/hexanes) provided pure DMB ether (+)-2.44 (3.52 g, 92%) as acolorless oil. [α]_(D) ²⁰+29.8 (c 1.8, CHCl₃); IR (CHCl₃) 2930 (m), 2856(m), 1516 (s), 1463 (m), 1389 (w), 1266 (s), 1238 (m), 1156 (m), 1112(s), 1030 (s), 822 (w), 738 (m), 702 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ7.66 (m, 4H), 7.40 (m, 6H), 6.87 (m, 3H), 6.17 (d, J=1.1 Hz, 1H), 4.57(d, J=11.2 Hz, 1H), 4.30 (d, J=11.2 Hz, 1H), 3.88 (s, 3H), 3.87 (s, 3H),3.78 (ddd, J=10.2, 8.6, 4.9 Hz, 1H), 3.72 (ddd, J=10.6, 10.2, 5.4 Hz,1H), 3.63 (ddd, J=8.2, 4.8, 1.9 Hz, 1H), 3.43 (d, J=10.3 Hz, 1H), 3.17(dd, J=10.4, 4.7 Hz, 1H), 2.08 (m, 1H), 1.83 (m, 1H), 1.80 (d, J=1.0 Hz,3H), 1.77 (m, 1H), 1.68 (m, 1H), 1.06 (s, 9H), 0.93 (d, J=6.9 Hz, 3H),0.80 (d, J=6.5 Hz, 3H); ¹³CNMR (125 MHz, CDCl₃) δ 149.0, 148.6, 146.7,135.6, 133.9, 133.8, 131.1, 129.6, 129.4, 127.6, 120.2, 111.2, 110.9,87.5, 83.2, 80.5, 74.9, 69.8, 60.6, 55.9, 55.8, 35.7, 34.2, 33.4, 26.9,19.2, 19.1, 13.6, 6.0; high resolution mass spectrum (ES⁺) m/z 751.2320[(M+Na)⁺; calcd for C₃₇H₄₉O₅SiINa: 751.2292].

Primary Alcohol (+)-2.S₃:

To a solution of BPS-protected tetrahydropyran (+)-2.44 (155.0 mg, 0.213mmol) in THF (2.1 mL) under argon was added tetrabutylammonium fluoride(1.0 M/THF) (426 mL, 0.426 mmol) at room temperature. After stirring forone hour, the reaction mixture was treated with saturated aqueous sodiumchloride (5 mL) and the solution was extracted with chloroform (10 mL,3×). The combined organic extracts were dried over Na₂SO₄, filtered andconcentrated under reduced pressure. Purification via silica gelchromatography (33% EtOAc/hexanes) afforded primary alcohol (+)-2.S₃(101.4 mg, 97%) as a colorless oil. [α]_(D) ²⁰+51.4 (c 0.8, CHCl₃); IR(CHCl₃) 3452 (b), 2934 (m), 2879 (m), 1594 (w), 1516 (s), 1464 (m), 1419(m), 1387 (m), 1265 (s), 1238 (s), 1156 (s), 1139 (s), 1093 (m), 1028(s), 807 (w), 766 (w) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 6.86 (m, 3H), 6.24(d, J=0.9 Hz, 1H), 4.57 (d, J=11.3 Hz, 1H), 4.31 (d, J=11.3 Hz, 1H),3.88 (s, 3H), 3.87 (s, 3H), 3.76 (m, 2H), 3.62 (ddd, J=9.8, 2.5, 2.3 Hz,1H), 3.55 (d, J=10.3 Hz, 1H), 3.18 (dd, J=10.4, 4.7 Hz, 1H), 2.31 (br s,1H), 2.04 (m, 1H), 1.97 (m, 1H), 1.80 (d, J=1.0 Hz, 3H), 1.79 (m, 1H),1.53 (m, 1H), 0.98 (d, J=6.9 Hz, 3H), 0.80 (d, J=6.5 Hz, 3H); ¹³CNMR(125 MHz, CDCl₃) δ 149.0, 148.7, 146.1, 130.9, 120.2, 111.2, 110.9,87.6, 82.6, 81.2, 78.7, 69.9, 61.7, 55.9, 55.8, 35.1, 34.8, 33.2, 19.1,13.5, 6.2; high resolution mass spectrum (ES⁺) m/z 513.1096 [(M+Na)⁺;calcd for C₂₁H₃₁O₅₁Na: 513.1114].

Aldehyde (+)-2.12:

To a solution of primary alcohol (+)-2.S₃ (0.415 g, 0.848 mmol) indichloromethane (8.5 mL) under argon was added methylsulfoxide (0.902mL, 12.7 mmol) and triethylamine (0.589 mL, 4.2 mmol) followed bycooling to 0° C. SO₃.Pyridine complex (0.337 g, 2.10 mmol) was added inone portion and after stirring for ten minutes, the reaction was warmedto room temperature. After two hours, the reaction was quenched withwater (5 mL), and extracted with diethyl ether (10 mL, 3×). The combinedorganic extracts were dried over Na₂SO₄, filtered and concentrated underreduced pressure. Purification via silica gel chromatography (40%EtOAc/hexanes) afforded aldehyde (+)-2.12 (0.384 g, 92%) as a whitesolid. mp. 98-100° C.; [α]_(D) ²⁰+36.7 (c 0.3, CHCl₃); IR (CHCl₃) 2959(w), 2926 (m), 2848 (m), 1725 (s), 1516 (s), 1464 (m), 1263 (s), 1157(m), 1075 (m), 1029 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 9.74 (app t,J=1.9 Hz, 1H), 6.84 (m, 3H), 6.22 (d, J=1.0 Hz, 1H), 4.56 (d, J=11.3 Hz,1H), 4.30 (d, J=11.3 Hz, 1H), 3.95 (ddd, J=8.6, 4.5, 2.2 Hz, 1H), 3.87(s, 3H), 3.86 (s, 3H), 3.53 (d, J=10.3 Hz, 1H), 3.20 (dd, J=10.4, 4.6Hz, 1H), 2.74 (ddd, J=16.8, 8.6, 1.9 Hz, 1H), 2.42 (ddd, J=16.8, 4.5,1.9 Hz, 1H), 2.10 (m, 1H), 1.78 (d, J=1.1 Hz, 3H), 1.76 (m, 1H), 0.95(d, J=6.9 Hz, 3H), 0.79 (d, J=6.5 Hz, 3H); ¹³CNMR (125 MHz, CDCl₃) δ200.7, 148.9, 148.6, 145.9, 130.7, 120.2, 111.1, 110.9, 87.5, 82.3,81.1, 73.2, 69.9, 55.9, 55.7, 46.7, 34.1, 33.0, 19.1, 13.5, 6.0; highresolution mass spectrum (ES⁺) m/z 511.0935 [(M+Na)⁺; calcd forC₂₁H₂₉O₅INa: 511.0957].

Mesylate (−)-2.52:

To known alcohol (−)-2.41 (Smith, et al. J. Am. Chem. Soc. 2001, 123,10942) (0.419 g, 0.595 mmol), stirring in dichloromethane (37 mL) underan argon atmosphere at −10° C. was added diisopropylethylamine (0.21 mL,1.2 mmol) followed by the dropwise addition of methanesulfonyl chloride(0.055 mL, 0.714 mmol). After forty minutes the reaction mixture waspurified directly via silica gel chromatography (15% EtOAc/hexanes→30%EtOAc/hexanes) to afford mesylate (−)-2.52 (0.461 g, 99%) as a colorlessoil. [α]_(D) ²⁰−10.5 (c 1.0, CHCl₃); IR (CHCl₃) 2951 (b), 2856 (s), 1363(s), 1552 (s), 1177 (s), 1111 (s), 1034 (b), 958 (s), 836 (s) cm⁻¹;¹HNMR (500 MHz, CDCl₃) δ 7.65 (m, 4H), 7.55 (s, 1H), 7.39 (m, 6H), 5.24(s, 2H), 4.86 (d, J=9.6 Hz, 1H), 4.72 (s, 2H), 4.20 (app t, J=2.6 Hz,1H), 4.01 (m, 2H), 3.75 (m, 1H), 3.70 (m, 1H), 3.07 (s, 3H), 2.35 (dd,J=13.2, 4.5 Hz, 1H), 2.31 (dd, J=13.2, 4.2 Hz, 1H), 2.03 (dd, J=13.1,5.9 Hz, 1H), 1.97 (dd, J=13.2, 6.8 Hz, 1H), 1.89 (m, 2H), 1.82 (m, 1H),1.74 (app t, J=11.8 Hz, 1H), 1.65 (m, 2H), 1.52 (m, 3H), 1.04 (s, 9H),0.91 (s, 9H), 0.07 (s, 6H); ¹³C NMR (125 MHz, CDCl₃) δ 156.6, 143.8,142.4, 136.9, 135.7, 134.1, 134.0, 129.7, 129.6, 127.8, 110.3, 69.4,69.2, 69.0, 67.5, 64.8, 62.2, 60.8, 39.8, 39.5, 39.4, 39.2, 38.6, 38.5,36.7, 27.0, 26.0, 19.4, 18.2, −4.5, −4.6; high resolution mass spectrum(ES⁺) m/z 806.3529 [(M+Na)⁺; calcd for C₄₁H₆INO₈SSi₂Na: 806.3517].

C(19-20)-E-Olefin (+)-2.46:

To a solution of mesylate (−)-2.52 (0.707 g, 0.901 mmol) in anhydrousDMF (192 mL) at room temperature under argon was added dropwise,tri-n-butylphosphine (0.901 mL, 3.61 mmol). After thirty six hours atroom temperature, aldehyde (+)-2.12 (0.439 g, 0.901 mmol) in anhydrousDMF (103 mL) was added dropwise via cannula followed by dropwiseaddition of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (0.272 mL, 1.80mmol). After stirring at room temperature for three hours, the reactionmixture was diluted with diethyl ether (80 mL) and poured into water(120 mL). The layers were separated and the aqueous layer was extractedwith diethyl ether (50 mL, 5×). The combined organic extracts werewashed with saturated aqueous sodium chloride (50 mL), dried over MgSO₄,filtered and concentrated under reduced pressure. Purification viasilica gel chromatography (20% EtOAc/hexanes) afforded theC(19-20)-E-olefin product (+)-2.46 (1.01 g, 96%, 20:1, E:Z) as a whitefoam. [α]_(D) ²⁰+22.7 (c 1.0, CHCl₃); IR (neat) 2967 (b), 2930 (s), 1487(m), 1258 (s), 1110 (s), 776 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.64 (m,4H), 7.35 (m, 6H), 6.89 (d, J=1.9 Hz, 1H), 6.82 (dd, J=8.2, 1.9 Hz, 1H),6.58 (m, 1H), 6.32 (d, J=16.0 Hz, 1H), 6.23 (s, 1H), 4.82 (dd, J=11.2,1.9 Hz, 1H), 4.70 (s, 2H), 4.56 (d, J=11.2 Hz, 1H), 4.26 (d, J=11.2 Hz,1H), 4.24, (m, 1H), 3.95 (m, 3H), 3.87 (s, 3H), 3.65 (m, 2H), 3.50 (d,J=10.4 Hz, 1H), 3.45 (ddd, J=14.1, 7.1, 1.8 Hz, 1H), 3.12 (dd, J=10.4,4.5 Hz, 1H), 2.52 (m, 1H), 2.34 (m, 3H), 2.08 (m, 1H), 2.00 (dd, J=13.0,7.0 Hz, 1H), 1.93 (dd, J=13.0, 7.0 Hz, 1H), 1.86 (m, 2H), 1.82 (s, 3H),1.80 (m, 2H), 1.75 (m, 4H), 1.61 (m, 3H), 1.48 (m, 3H), 1.06 (s, 9H),0.97 (d, J=6.7 Hz, 3H), 0.91 (s, 9H), 0.76 (d, J=6.3 Hz, 3H), 0.06 (s,6H); ¹³CNMR (125 MHz, CDCl₃) δ 160.7, 149.0, 148.6, 146.3, 143.3, 142.3,135.6, 135.5, 135.1, 134.2, 133.9, 133.8, 130.9, 129.5, 127.6, 120.2,118.8, 111.1, 110.1, 87.5, 82.8, 80.9, 77.4, 77.2, 69.9, 69.0, 68.8,67.4, 64.7, 60.6, 55.9, 55.7, 39.6, 39.3, 39.2, 38.9, 38.2, 36.6, 36.2,33.7, 33.5, 33.3, 30.3, 26.8, 25.8, 19.1, 18.0, 13.5, 5.7, −4.8, −4.9;high resolution mass spectrum (ES⁺) m/z 1182.4735 [(M+Na)⁺; calcd forC₆₁H₈₆INO₉Si₂Na: 1182.4886].

Primary Alcohol (+)-2.54:

Under an argon atmosphere, a solution of C(19-20)-E-olefin product(+)-2.46 (0.153 g, 0.132 mmol) in THF (18 mL) was added dropwise viacannula to a solution of potassium hydroxide (0.627 g, 11.0 mmol), and18-crown-6 (1.04 g, 3.95 mmol) in THF (20 mL) and water (1.5 mL) at 0°C. After forty minutes, the solution was warmed to room temperature andafter five hours, the reaction mixture was poured over saturated aqueoussodium chloride (25 mL) and extracted with ethyl acetate (15 mL, 3×).The combined organic extracts were dried over MgSO₄ and concentrated invacuo. Purification via silica gel chromatography (40% EtOAc/hexanes)afforded primary alcohol (+)-2.54 (0.106 g, 87%) as a colorless oil.[α]_(D) ²⁰+25.0 (c 1.0, CHCl₃); IR (neat) 2927 (b), 2831 (s), 1516 (s),1464 (m), 1258 (b), 1031 (m), 835 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ7.46 (s, 1H), 6.82 (m, 3H), 6.59 (ddd, J=15.6, 8.6, 6.7 Hz, 1H), 6.33(d, J=16.0 Hz, 1H), 6.23 (s, 1H), 4.83 (dd, J=10.8, 2.6 Hz, 1H), 4.76(s, 1H), 4.72 (s, 1H), 4.56 (d, J=11.5 Hz, 1H), 4.27 (m, 1H), 4.26 (d,J=11.2 Hz, 1H), 4.06 (m, 1H), 4.01 (m, 1H), 3.95 (m, 1H), 3.87 (s, 6H),3.71 (m, 2H), 3.50 (d, J=10.1 Hz, 1H), 3.45 (ddd, J=13.1, 6.7, 1.9 Hz,1H), 3.13 (dd, J=10.1, 4.5 Hz, 1H), 2.52 (m, 1H), 2.33 (m, 3H), 2.26(dd, J=13.4, 4.1 Hz, 1H), 2.08 (m, 1H), 2.00 (m, 2H), 1.92 (m, 1H), 1.82(s, 3H), 1.76 (m, 4H), 1.48 (m, 4H), 0.95 (d, J=7.1 Hz, 3H), 0.91 (s,9H), 0.78 (d, J=6.7 Hz, 3H), 0.08 (s, 3H), 0.07 (s, 3H); ¹³CNMR (125MHz, CDCl₃) δ 161.3, 149.0, 148.6, 146.5, 142.8, 142.1, 141.8, 136.6,134.6, 131.2, 120.5, 118.5, 111.5, 111.3, 110.6, 87.8, 83.1, 81.1, 77.7,77.3, 70.8, 70.2, 70.1, 67.3, 65.0, 60.4, 56.2, 56.0, 40.3, 39.4, 39.0,38.9, 38.1, 36.5, 36.4, 33.9, 33.5, 26.1, 19.4, 18.1, 13.7, 5.9, −4.6;high resolution mass spectrum (ES⁺) m/z 944.3605 [(M+Na)⁺; calcd forC₄₅H₆₈INO₉SiNa: 944.3652].

Aldehyde (+)-2.55:

To a solution of alcohol (+)-2.54 (61.0 mg, 0.066 mmol) indichloromethane (24 mL) under argon at 0° C. was added solid sodiumbicarbonate (5.5 mg, 0.066 mmol) followed by Dess-Martin periodinane(56.0 mg, 0.132 mmol). After thirty minutes, the reaction was warmed toroom temperature and after two total hours of reaction, the solution waspoured into saturated aqueous sodium bicarbonate (15 mL) and the layerswere separated. The aqueous layer was extracted with dichloromethane (15mL, 3×), dried over MgSO₄ and concentrated under reduced pressure.Purification via silica gel chromatography (30% EtOAc/hexanes) affordedaldehyde (+)-2.55 (59.4 mg, 98%) as a colorless oil. [α]_(D) ²⁰+35.0 (c1.0, CHCl₃); IR (neat) 2931 (b), 2851 (s), 1724 (s), 1510 (s), 1461 (s),1366 (m), 1257 (b), 1098 (b), 1028 (s), 914 (b), 834 (s) cm⁻¹; ¹HNMR(500 MHz, CDCl₃) δ 9.74 (app t, J=2.6 Hz, 1H), 7.47 (s, 1H), 6.82 (m,3H), 6.59 (m, 1H), 6.32 (s, 1H), 4.83 (dd, J=8.9, 5.2 Hz, 1H), 4.79 (s,1H), 4.77 (s, 1H), 4.56 (d, J=11.2 Hz, 1H), 4.31 (m, 1H), 4.25 (d,J=10.8 Hz, 1H), 4.24 (m, 1H), 4.00 (m, 2H), 3.87 (s, 6H), 3.49 (d,J=10.4 Hz, 1H), 3.45 (ddd, J=7.4, 7.4, 1.8 Hz, 1H), 3.12 (dd, J=10.0,4.8 Hz, 1H), 2.64 (dd, J=7.8, 3.0 Hz, 1H), 2.61 (dd, J=7.8, 2.6 Hz, 1H),2.52 (m, 1H), 2.48 (dd, J=6.0, 2.2 Hz, 1H), 2.45 (dd, J=6.0, 1.9 Hz,1H), 2.32 (m, 3H), 2.08 (m, 2H), 1.95 (m, 2H), 1.82 (s, 2H), 1.75 (m,3H), 1.43 (m, 3H), 0.95 (d, J=7.1 Hz, 3H), 0.91 (s, 9H), 0.79 (d, J=6.7Hz, 3H), 0.07 (s, 3H), 0.06 (s, 3H); ¹³CNMR (125 MHz, CDCl₃) δ 200.9,160.9, 149.0, 148.6, 146.3, 143.1, 140.9, 136.1, 135.3, 134.2, 131.9,120.2, 118.7, 111.1, 110.9, 87.5, 82.8, 80.9, 77.4, 77.1, 69.9, 69.6,69.1, 67.3, 67.2, 64.6, 55.9, 55.7, 47.7, 39.6, 38.9, 38.8, 38.0, 36.2,33.6, 33.3, 29.6, 25.8, 19.1, 13.5, 5.7, −4.9, −5.0; high resolutionmass spectrum (ES⁺) m/z 942.3552 [(M+Na)⁺; calcd for C₄₅H₆₆INO₉SiNa:942.3455].

Secondary Alcohol-Aldehyde (+)-2.10:

To a solution of aldehyde (+)-2.55 (59.4 mg, 0.064 mmol) indichloromethane (10 mL) and pH 7 buffer (2.7 mL) under an argonatmosphere at room temperature was added2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) (29.3 mg, 0.129 mmol).After stirring for four hours, the reaction was poured over saturatedaqueous sodium bicarbonate (10 mL), extracted with dichloromethane (8mL, 3×), dried over MgSO₄, filtered and concentrated under reducedpressure. Purification via silica gel chromatography (25% EtOAc/hexanes)afforded secondary alcohol-aldehyde (+)-2.10 (50.6 mg, 95%) as acolorless oil. [α]_(D) ²⁰+34.0 (c 0.1, CHCl₃); IR (neat) 3429 (b), 2924(s), 2853 (s), 1725 (s), 1461 (s), 1377 (m), 1252 (s), 1098 (s), 1049(b), 900 (b), 835 (s), 776 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 9.74 (appt, J=2.2 Hz, 1H), 7.45 (s, 1H), 6.56 (m, 1H), 6.30 (d, J=16.0 Hz, 1H),6.24 (s, 1H), 4.81 (app t, J=7.4 Hz 1H), 4.79 (s, 1H), 4.77 (s, 1H),4.31 (m, 1H), 4.24 (br s, 1H), 3.99 (m, 2H), 3.48 (m, 1H), 3.47 (d,J=10.3 Hz, 1H), 3.41 (dd, J=10.4, 4.8 Hz, 1H), 2.64 (dd, J=7.8, 2.6 Hz,1H), 2.51 (m, 1H), 2.48 (dd, J=6.0, 2.2 Hz, 1H), 2.39 (dd, J=6.0, 1.9Hz, 1H), 2.29 (m, 3H), 1.96 (m, 3H), 1.88 (m, 1H), 1.83 (s, 3H), 1.80(m, 2H), 1.44 (m, 4H), 0.94 (d, J=6.7 Hz, 3H), 0.91 (s, 9H), 0.80 (d,J=6.7 Hz, 3H), 0.07 (s, 3H), 0.06 (s, 3H); ¹³CNMR (125 MHz, CDCl₃) δ200.9, 161.3, 146.6, 143.6, 135.8, 134.7, 119.2, 111.6, 87.8, 81.4,78.2, 70.1, 69.6, 67.8, 67.7, 65.1, 48.2, 40.1, 39.5, 39.4, 39.3, 39.1,38.6, 38.4, 36.4, 35.1, 30.1, 26.3, 19.7, 18.5, 13.6, 5.9, −4.3, −4.4;high resolution mass spectrum (ES⁺) m/z 792.2767 [(M+Na)⁺; calcd forC₃₆H₅₆INO₇SiNa: 792.2736].

Phosphonate Ester (+)-2.56:

To a solution of secondary alcohol-aldehyde (+)-2.10 (30.5 mg, 0.039mmol) in dichloromethane (7.3 mL) under an argon atmosphere at roomtemperature was added dropwise via cannula, trifluoroethylphosphonateacid 3.45 (59.0 mg, 0.195 mmol) as a solution in dichloromethane (7.3mL) and allowed to stir for five minutes.1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide methiodide (EDCI.MeI)(58.9 mg, 0.198 mmol) followed by hydroxybenzatriazole (HOBT)(catalytic) were added and the reaction was allowed to stir at roomtemperature. After thirty minutes, the reaction solution wasconcentrated under reduced pressure to ½ volume and purified directlyvia silica gel chromatography (40% EtOAc/hexanes) to afford phosphonateester (+)-2.56 (38.3 mg, 93%) as a colorless oil. [α]_(D) ²⁰+20.0 (c0.1, CHCl₃); IR (neat) 2928 (b), 1734 (s), 1268 (b), 1174 (s), 1098 (m),963 (s), 893 (b), 835 (s), 775 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 9.74(app t, J=2.2 Hz, 1H), 7.45, (s, 1H), 6.53 (m, 1H), 6.29 (d, J=16 Hz,1H), 6.28 (s, 1H), 4.82 (app t, J=7.1 Hz, 1H), 4.79 (s, 1H), 4.77 (s,1H), 4.72 (dd, J=11.2, 4.8 Hz, 1H), 4.39 (m, 4H), 4.31 (m, 1H), 4.24 (brs, 1H), 3.99 (m, 2H), 3.56 (m, 2H), 3.19 (s, 1H), 3.14 (s, 1H), 2.64(dd, J=7.4, 2.6 Hz, 1H), 2.60 (dd, J=7.8, 2.9 Hz, 1H), 2.55 (m, 1H),2.45 (m, 2H), 2.25 (m, 3H), 2.07 (m, 2H), 1.96 (m, 4H), 1.86 (m, 2H),1.84 (m, 2H), 1.83 (s, 3H), 1.61 (m, 2H), 1.46 (m, 3H), 0.95 (d, J=6.7Hz, 3H), 0.91, (s, 9H), 0.72 (d, J=6.4 Hz, 3H), 0.07 (s, 3H), 0.06 (s,3H); ¹³CNMR (125 MHz, CDCl₃) δ 200.9, 163.9, 160.7, 145.3, 143.1, 140.8,134.6, 134.2, 119.0, 111.1, 87.1, 81.7, 80.5, 77.1, 77.0, 69.6, 69.0,67.3, 67.2, 64.6, 62.5, 62.4, 47.7, 39.6, 38.9, 38.8, 38.7, 38.1, 35.8,35.2, 34.6, 33.5, 32.0, 29.6, 25.8, 19.1, 18.0, 12.9, 6.0, −4.9, −5.0;high resolution mass spectrum (ES⁺) m/z 1078.2700 [(M+Na)⁺; calcd forC₄₅H₆₈INO₉SiNa: 1078.2657].

Z-C(2-3)-Macrocycle (+)-2.5:

To a flask charged with freshly distilled toluene (34 mL) at roomtemperature under argon was added 18-crown-6 (0.710 g, 2.70 mmol) andpotassium carbonate (79.0 mg, 0.576 mmol). After stirring for threehours, a solution of phosphonate ester (+)-2.56 (50.7 mg, 0.048 mmol) intoluene (34 mL) was added dropwise via cannula and allowed to stir atroom temperature. After three hours, the reaction mixture was pouredinto saturated aqueous sodium chloride (30 mL) and the resultant layersof the biphasic mixture were separated. The aqueous layer was extractedwith ethyl acetate (20 mL, 3×) and the combined organic extracts weredried over MgSO₄ and concentrated in vacuo. Purification by preparativethin layer chromatography (30% EtOAc/hexanes) affordedZ-C(2-3)-macrocycle (+)-2.5 (22.2 mg, 68% yield) as a white foam andE-C(2-3)-macrocycle (+)-2.S₄ (10.5 mg, 29%) as a light yellow oil. Total(32.7 mg, 96%, 2.5:1 Z:E). Z-C(2-3)-Macrocycle (+)-2.5: [α]_(D) ²⁰+47.5(c 0.3, CHCl₃); IR (neat) 2926 (s), 2854 (s), 1718 (s), 1252 (s), 1186(s), 1091 (s), 1034 (m), 835 (s) cm⁻¹; ¹HNMR (500 MHz, C₆D₆) δ 6.94 (s,1H), 6.84 (m, 1H), 6.16 (d, J=15.9 Hz, 1H), 6.02 (s, 1H), 5.76 (dd,J=13.4, 11.2 Hz, 1H), 5.43 (ddd, J=10.4, 10.4, 2.8 Hz, 1H), 5.16 (s,1H), 4.95 (d, J=11.3 Hz, 1H), 4.72 (s, 1H), 4.48 (dd, J=15.5, 11.2 Hz,1H), 4.38 (m, 1H), 4.24 (app t, J=10.8 Hz, 1H), 4.06 (m, 1H), 4.00 (appt, J=2.5 Hz, 1H), 3.94 (m, 1H), 3.27 (m, 1H), 3.24 (d, J=10.2 Hz, 1H),3.04 (d, J=11.9 Hz, 1H), 2.57 (app t, J=6.4 Hz, 1H), 2.41 (d, J=3.1 Hz,1H), 2.32 (m, 2H), 2.09 (ddd, J=13.1, 11.8, 5.0 Hz, 1H), 1.99 (app t,J=11.8 Hz, 1H), 1.94 (d, J=12.9 Hz, 1H), 1.84 (m, 1H), 1.79 (d, J=0.9Hz, 3H), 1.63 (m, 3H), 1.47 (d, J=13.4 Hz, 1H), 1.33 (m, 2H), 0.93 (d,J=6.8 Hz, 3H), 0.92 (s, 9H), 0.57 (d, J=6.5 Hz, 3H), 0.00 (s, 3H), −0.01(s, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 165.7, 161.6, 146.7, 145.8, 143.8,143.0, 134.1, 133.8, 121.2, 120.2, 110.4, 88.1, 81.5, 79.7, 78.8, 73.6,69.9, 69.3, 67.6, 65.8, 42.4, 40.5, 39.9, 37.9, 36.3, 34.7, 33.0, 32.3,31.1, 26.3, 19.6, 18.6, 13.3, 6.5, −4.4, −4.5; high resolution massspectrum (ES⁺) m/z 816.2741 [(M+Na)⁺; calcd for C₃₈H₅₆INO₇SiNa:816.2763].

E-C(2-3)-Macrocycle (+)-2.S₄: [α]_(D) ²⁰+26.7 (c 0.9, CHCl₃); IR (neat)2933 (b), 2794 (s), 1718 (s), 1654 (s), 1252 (m), 1152 (s), 1087 (m),1024 (s), 833 (s), 775 (s) cm⁻¹; ¹HNMR (500 MHz, C₆D₆) δ 7.20 (m, 1H),6.90 (s, 1H), 6.83 (m, 1H), 6.11 (d, J=15.7 Hz, 1H), 6.01 (d, J=15.2 Hz,1H), 5.95 (s, 1H), 4.93 (d, J=11.6 Hz, 1H), 4.94 (m, 1H), 4.67 (s, 1H),4.58 (s, 1H), 4.34 (br s, 1H), 3.99 (s, 1H), 3.90 (app q, J=7.1 Hz, 1H),3.37 (app t, J=9.1 Hz, 1H), 3.31 (m, 1H), 3.19 (d, J=10.0 Hz, 1H), 2.41(d, J=13.9 Hz, 1H), 2.26 (m, 2H), 2.12 (d, J=10.6 Hz, 1H), 2.08 (d,J=10.5 Hz, 1H), 2.02 (m, 1H), 1.89 (dd, J=13.0, 2.6 Hz, 1H), 1.80 (m,3H), 1.75 (d, J=1.0 Hz, 3H), 1.67 (m, 3H), 1.61 (m, 1H), 1.35 (m, 2H),0.96 (m, 9H), 0.74 (d, J=6.7 Hz, 3H), 0.66 (d, J=6.5 Hz, 3H), 0.00 (s,3H), −0.01 (s, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 167.3, 162.4, 147.6, 146.9,143.9, 142.8, 135.7, 134.6, 124.1, 119.2, 111.4, 88.1, 81.5, 78.8, 77.4,71.0, 70.0, 68.7, 66.4, 66.2, 41.6, 41.3, 40.4, 38.8, 38.6, 38.5, 35.8,35.3, 33.2, 26.6, 26.5, 19.8, 18.8, 13.6, 6.1, −4.2; high resolutionmass spectrum (ES⁺) m/z 816.2788 [(M+Na)⁺; calcd for C₃₈H₅₆INO₇SiNa:816.2763].

C(45-46)-TMS-Alkynyl Sidechain (−)-2.90:

Known oxazole triflate, (−)-2.S5 (Smith, et al. J. Am. Chem. Soc. 2001,123, 10942) (69.6 mg, 0.089 mmol) was combined with hexamethylditin(0.026 mL, 0.125 mmol) in a 100 mL sealed tube and azeotroped frombenzene (5 mL, 3×) followed by drying under vacuum for one hour. In aglove bag, under an inert argon atmosphere to the sealed tube was added,flame dried lithium chloride (60.0 mg, 1.40 mmol),tetrakis(triphenylphosphine)palladium [Pd(PPh₃)₄] (15.0 mg, 0.013 mmol)and dioxane (0.90 mL), (freeze pump thawed, 3×). The reaction was heatedto 90° C. behind a blast shield and after fifteen hours, the reactionwas cooled to room temperature and purified directly via silica gelchromatography (15% EtOAc/hexanes) to afford C(45-46)-TMS-alkynylsidechain (−)-2.90 (46.4 mg, 64%) as a colorless oil. [α]_(D) ²⁰−37.5 (c0.1, CH₂Cl₂); IR (neat) 2927 (s), 2865 (s), 1462 (m), 1248 (s), 1093(b), 843 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.45 (s, 1H), 6.24 (d,J=15.7 Hz, 1H), 5.55 (dd, J=15.6, 7.6 Hz, 1H), 5.43 (d, J=8.8 Hz, 1H),4.63 (dd, J=8.7, 6.1 Hz, 1H), 3.78 (app q, J=3.2 Hz, 1H), 3.57 (m, 3H),3.34 (s, 3H), 3.31 (s, 3H), 3.29 (s, 3H), 3.03 (d, J=14.9 Hz, 1H), 2.58(dd, J=16.7, 5.7 Hz, 1H), 2.44 (dd, J=16.7, 6.8 Hz, 1H), 2.20 (dddd,J=12.7, 4.6, 4.5, 1.6 Hz, 1H), 2.00 (dd, J=12.2, 4.4 Hz, 1H), 1.78 (d,J=0.9 Hz, 3H), 1.37 (dd, J=12.6, 11.2 Hz, 1H), 1.06 (m, 22H), 0.31 (s,9H), 0.14 (s, 9H); ¹³CNMR (125 MHz, CDCl₃) δ 160.9, 145.1, 137.2, 134.1,133.0, 127.4, 103.2, 99.9, 86.4, 80.6, 73.8, 73.5, 71.7, 56.5, 55.5,47.8, 39.2, 35.6, 32.0, 29.6, 27.0, 18.0, 17.9, 13.6, 12.3, 0.04; highresolution mass spectrum (ES⁺) m/z 820.3400 [(M+Na)⁺; calcd forC₃₇H₆₇NO₆Si₂SnNa: 820.3426].

Protected C(45-46)-TMS-Alkynyl-Phorboxazole (+)-3.35:

Vinyliodide macrocycle (+)-2.5 (13.8 mg, 0.017 mmol) andC(45-46)-TMS-alkynyl side chain (−)-2.90 (21.0 mg, 0.026 mmol) werecombined in a flame dried round bottom flask (5 mL), azeotroped frombenzene (2 mL, 3×) and dried under vacuum for two hours. To the flaskunder an argon atmosphere were addedtris(dibenzylideneacetone)dipalladium-chloroform adduct[Pd₂(dba)₃.CHCl₃] (3.6 mg, 0.003 mmol), triphenylarsine (AsPh₃) (6.4 mg,0.021 mmol) and Ph₂PO₂NBu₄. (12 mg, 0.026 mmol) followed by introductionof DMF (0.17 mL, sparged with argon, thirty minutes) anddiisopropylethylamine (0.003 mL, 0.017 mmol). After the reaction wasallowed to stir for sixteen hours at room temperature, the light brownreaction mixture was introduced directly onto a silica gel column, (20%EtOAc/hexanes→30% EtOAc/hexanes) to afford protectedC(45-46)-TMS-alkynyl-phorboxazole (+)-3.35 (14.9 mg, 68%) as a lightyellow oil. [α]_(D) ²⁰+1.3 (c 0.2, CHCl₃); IR (neat) 2925 (b), 1718 (s),1456 (b), 1250 (s), 1187 (s), 1091 (s), 1053 (b), 840 (s) cm⁻¹; ¹HNMR(500 MHz, C₆D₆) δ 6.96 (s, 1H), 6.90 (m, 1H), 6.37 (s, 1H), 6.32 (d,J=15.7 Hz, 1H), 6.20 (d, J=15.9 Hz, 1H), 5.79 (dd, J=11.2, 2.3 Hz, 1H),5.69 (dd, J=15.7, 7.3 Hz, 1H), 5.57 (d, J=8.9 Hz, 1H), 5.47 (ddd,J=10.7, 10.5, 2.9 Hz, 1H), 5.18 (s, 1H), 4.96 (dd, J=11.3, 2.0 Hz, 1H),4.77 (m, 2H), 4.62 (dd, J=11.2, 4.4 Hz, 1H), 4.39 (m, 1H), 4.25 (app t,J=10.4 Hz, 1H), 4.08 (m, 1H), 4.03 (d, J=2.6 Hz, 1H), 3.95 (m, 1H), 3.76(m, 1H), 3.69 (app t, J=6.9 Hz, 1H), 3.68 (m, 1H), 3.52 (dd, J=9.4, 4.6Hz, 1H), 3.45 (d, J=10.1 Hz, 1H), 3.41 (s, 3H), 3.34 (d, J=14.7 Hz, 1H),3.28 (app t, J=4.8 Hz, 1H), 3.23 (app t, J=5.0 Hz, 1H), 3.09 (s, 3H),3.08 (s, 3H), 3.04 (d, J=11.4 Hz, 1H), 2.95 (d, J=14.8 Hz, 1H), 2.66(app t, J=6.3 Hz, 1H), 2.60 (m, 1H), 2.58 (dd, J=16.7, 5.7 Hz, 1H), 2.44(dd, J=16.7, 6.8 Hz, 1H), 2.42 (m, 2H), 2.37 (dd, J=12.8, 5.5 Hz, 1H),2.17 (dd, J=10.0, 7.7 Hz, 1H), 2.10 (m, 1H), 2.09 (d, J=0.6 Hz, 3H),2.02 (d, J=11.8 Hz, 1H), 1.98 (d, J=13.0 Hz, 1H), 1.77 (d, J=0.8 Hz,3H), 1.65 (m, 3H), 1.49 (d, J=13.2 Hz, 1H), 1.35 (m, 3H), 1.17 (m, 22H),1.05 (d, J=6.9 Hz, 3H), 0.94 (s, 9H), 0.77 (d, J=6.5 Hz, 3H), 0.24 (s,9H), 0.03 (s, 3H), 0.01 (s, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 165.8, 161.7,160.0, 145.5, 143.8, 143.0, 139.2, 138.2, 137.3, 136.8, 135.0, 134.4,133.8, 133.5, 121.4, 120.1, 119.5, 110.5, 104.6, 100.8, 90.0, 86.8,81.0, 80.2, 78.7, 74.7, 74.1, 73.7, 72.7, 69.9, 69.3, 67.7, 65.9, 56.7,55.6, 48.3, 42.4, 40.5, 40.4, 40.0, 37.9, 36.4, 36.3, 34.9, 33.1, 32.4,31.2, 30.5, 27.9, 26.3, 18.7, 18.6, 14.6, 14.1, 13.7, 13.2, 6.6, 1.7,0.6, −4.5, −4.4; high resolution mass spectrum (ES⁺) m/z 1321.7641[(M+Na)⁺; calcd for C₇₂H₁₁₄N₂O₁₃Si₃Na: 1321.7626].

Bromoalkyne (+)-2.92:

Protected C(45-46)-TMS-alkynyl-phorboxazole (+)-3.35 (4.4 mg, 0.0034mmol) was introduced into a flame dried round bottom flask, azeotropedfrom benzene (2 mL, 3×) and dried under vacuum. After one hour, under anargon atmosphere, (+)-3.35 was stirred in HPLC grade acetone (2.1 mL) at0° C. After five minutes, silver nitrate (catalytic) followed byN-bromosuccinimide (NBS) (3.3 mg, 0.018 mmol) were added and afterthirty minutes, the reaction mixture was warmed to room temperature.After two hours and thirty minutes of total reaction time, the reactionsolution was re-cooled to 0° C. and quenched via dropwise addition ofsaturated aqueous sodium thiosulfate (2 mL), stirred until the initialyellow color dissipated and then poured into saturated aqueous sodiumbicarbonate (5 mL). The layers of the biphasic mixture were separatedand the aqueous layer was extracted with dichloromethane (8 mL, 3×),dried over MgSO₄, filtered and concentrated under reduced pressure.Purification via silica gel chromatography (40% EtOAc/hexanes) affordedbromoalkyne (+)-2.92 (4.2 mg, 95%) as a white amorphous solid. [α]_(D)²⁰+3.1 (c 0.04, CH₂Cl₂); IR (neat) 2921 (b), 2861 (s), 1719 (s), 1461(m), 1371 (m), 1187 (s), 1093 (s), 884 (w); ¹HNMR (500 MHz, C₆D₆) δ 7.20(s, 1H), 6.95 (s, 1H), 6.88 (m, 1H), 6.35 (s, 1H), 6.23 (d, J=15.8 Hz,1H), 6.19 (d, J=15.8 Hz, 1H), 5.79 (dd, J=11.2, 2.5 Hz, 1H), 5.54 (d,J=10.7 Hz, 1H), 5.53 (dd, J=15.3, 7.3 Hz, 1H), 5.45 (ddd, J=10.7, 10.7,2.7 Hz, 1H), 5.17 (s, 1H), 4.95 (d, J=11.2 Hz, 1H), 4.74 (s, 1H), 4.73(m, 1H), 4.61 (dd, J=11.2, 4.3 Hz, 1H), 4.39 (m, 1H), 4.23 (m, 1H), 4.06(m, 1H), 4.02 (m, 1H), 3.97 (m, 1H), 3.75 (ddd, J=12.1, 7.8, 1.8 Hz,1H), 3.69 (m, 1H), 3.54 (dd, J=13.2, 6.6 Hz, 1H), 3.43 (d, J=9.9 Hz,1H), 3.40 (s, 3H), 3.33 (d, J=14.7 Hz, 1H), 3.07 (s, 3H), 3.04 (s, 3H),2.94 (d, J=14.8 Hz, 1H), 2.65 (m, 1H), 2.56 (dd, J=12.9, 3.3 Hz, 1H),2.42 (m, 4H), 2.37 (dd, J=16.7, 5.7 Hz, 1H), 2.24 (dd, J=16.6, 6.7 Hz,1H), 2.14 (m, 1H), 2.08 (s, 3H), 2.03 (d, J=11.4 Hz, 1H), 1.97 (m, 1H),1.70 (d, J=0.8 Hz, 3H), 1.63 (m, 5H), 1.48 (d, J=13.3 Hz, 1H), 1.34 (m,5H), 1.16 (m, 21H), 1.04 (d, J=6.8 Hz, 3H), 0.92 (s, 9H), 0.76 (d, J=6.4Hz, 3H), 0.09 (s, 3H), −0.01 (s, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 165.1,161.1, 159.4, 144.9, 143.2, 142.3, 138.7, 137.6, 137.1, 136.1, 134.1,133.9, 133.2, 133.1, 120.8, 119.6, 118.8, 109.8, 100.3, 89.4, 80.2,79.6, 78.2, 77.1, 74.1, 73.1, 72.0, 69.3, 68.6, 67.1, 65.3, 56.0, 55.0,47.7, 47.6, 41.8, 39.9, 39.8, 39.7, 39.3, 37.3, 35.7, 35.5, 34.3, 32.5,31.8, 30.5, 29.9, 26.9, 25.7, 18.0, 17.8, 13.9, 13.4, 13.1, 12.7, 6.0,−5.0, −5.1; high resolution mass spectrum (ES⁺) m/z 1327.6339 [(M+Na)⁺;calcd for C₆₉H₁₀₅O₁₃N₂Si₂BrNa: 1327.6343].

Phorboxazole A (+)-1:

In a flame dried round bottom flask, bromoalkyne (+)-2.92 (4.2 mg,0.0032 mmol) was azeotroped from benzene (2 mL, 3×) and dried undervacuum. After one hour, under an argon atmosphere at room temperature,(+)-2.92 was dissolved in freshly distilled THF (1.5 mL) followed by theaddition of bis(triphenylphosphine)palladium(II) chloride [PdCl₂(PPh₃)₂](0.25 mL, 0.0006 mmol of stock solution; 2.0 mg/1.0 mL THF) andtri-n-butyltin hydride (0.002 mL, 0.0071 mmol). After fifteen minutes,tri-n-butyltin hydride (0.002 mL, 0.0071 mmol) was added and allowed tostir for twenty minutes at which time, the reaction was quenched viadropwise addition of saturated aqueous sodium bicarbonate (5 mL). Thelayers of the bisphasic mixture were separated and the aqueous layer wasextracted with dichloromethane (8 mL, 3×). The combined organic extractswere dried over MgSO₄, filtered and concentrated under reduced pressure.Filtration through a plug of silica gel (20% EtOAc/hexanes) andconcentration under reduced pressure afforded vinylstannane 2.S₆.

Vinylstannane 2.S₆, under an argon atmosphere was dissolved in anhydrousacetonitrile (2.0 mL) and cooled to 0° C. After five minutes,N-bromosuccinimide (NBS) (1.8 mg, 0.001 mmol) was added and followingthirty minutes, the reaction was quenched via dropwise addition ofsaturated aqueous sodium thiosulfate (3 mL) and stirred until theresultant yellow color dissipated. The solution was poured intosaturated aqueous sodium bicarbonate (5 mL) and extracted withdichloromethane (5 mL, 4×). The combined organic extracts were driedover MgSO₄, filtered and concentrated under reduced pressure. Filtrationthrough a plug of silica gel (40% EtOAc/hexanes) and concentration underreduced pressure afforded protected phorboxazole A 2.S₇.

Protected phorboxazole A 2.S₇ under an argon atmosphere was dissolved infreshly distilled THF (1.7 mL) followed by the dropwise addition of 6%HCl (0.67 mL) at room temperature. After ninety six hours, the reactionmixture was cooled to 0° C. and poured into saturated aqueous sodiumbicarbonate (5 mL) and extracted with dichloromethane (5 mL, 3×)followed by ethyl acetate (5 mL, 3×). The combined organic extracts weredried over MgSO₄, filtered and concentrated under reduced pressure.Purification via silica gel chromatography (100% EtOAc→10%methanol/EtOAc) afforded phorboxazole A (+)-1 (1.1 mg, 6:1-C(46):C(45)vinyl bromide). Further purification via reverse phase HPLC (ZORBAX C₁₈column, acetonitrile/H₂O (55/45) eluent) afforded phorboxazole A (+)-1(0.90 mg, 35% over 3-steps after HPLC purification) which matched the¹HNMR, [α]_(D) ²⁰, and high resolution mass spectrum of natural(+)-phorboxazole A: [α]_(D) ²⁰+43.4 (c 0.04, CH₂Cl₂), high resolutionmass spectrum (ES⁺) m/z 1045.4029 [(M+Na)⁺; calcd for C₅₃H₇₁N₂O₁₃Na:1045.4037].

Alcohol (−)-3.S₁:

Dry copper(I) cyanide (23 mg, 0.259 mmol) was added to a solution ofethylmagnesium bromide (1.0 M/THF) (16.2 mL, 16.2 mmol) in freshlydistilled THF (26 mL) at 0° C. under argon. After stirring for fiveminutes, the solution was cooled to −15° C. where known epoxide (−)-3.30(Cywin, et al. J. Org. Chem. 1991, 56, 2953) (2.45 g, 12.9 mmol) infreshly distilled THF (10.0 mL) was added dropwise via cannula. Afterstirring for fifteen minutes, the reaction mixture was poured intosaturated aqueous ammonium chloride (20 mL), extracted with ethylacetate (15 mL, 3×), dried over MgSO₄, filtered and concentrated invacuo. Purification via silica gel chromatography (5% EtOAc/hexanes)afforded alcohol (−)-3.S₁ (2.59 g, 92%) as a colorless oil. [α]_(D)²⁰−41.7 (c 0.67, CHCl₃); IR (neat) 2927 (m), 1465 (s), 1254 (s), 1097(s), 838 (s), 780 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 3.64 (m, 1H), 3.62(dd, J=9.6, 2.3 Hz, 1H), 3.38 (ddd, J=8.9, 7.9, 0.7 Hz, 1H), 2.38 (br s,1H), 1.41 (m, 4H), 0.93 (app t, J=6.8 Hz, 3H), 0.90 (s, 9H), 0.07 (s,6H); ¹³CNMR (125 MHz, CDCl₃) δ 71.5, 67.2, 34.9, 25.8, 18.7, 18.2, 14.1,−5.3, −5.4; high resolution mass spectrum (C₁, NH₃) m/z 219.1777 [(M)⁺;calcd for C₁₁H₂₆O₂Si: 219.1701].

TBS Ether (−)-3.31:

To a stirred solution of (−)-3.S₁ (1.24 g, 5.70 mmol) in dichloromethane(9.6 mL) under argon at room temperature was added2,6-di-tert-butyl-4-methylpyridine (2,6-DTBMP) (1.75 g, 8.50 mmol) inone portion followed by the dropwise addition ofmethyltrifluoromethylsulfonate (3.22 mL, 28.5 mmol). After stirring forseventeen hours at room temperature, the light brown reaction mixturewas filtered through a pad of Celite followed by washing withdichloromethane (10 mL, 3×). The filtrate was washed with saturatedaqueous sodium bicarbonate (20 mL) and the resultant aqueous layer wasextracted with dichloromethane (15 mL, 3×). The combined organicextracts were dried over MgSO₄, filtered and concentrated in vacuo.Purification via silica gel chromatography (10% Et₂O/hexanes) afforded(−)-3.31 (0.77 g, 58%) as a colorless oil. [α]_(D) ²⁰−32.6 (c 0.41,CHCl₃); IR (neat) 2951 (m), 2857 (s), 1463 (s), 1249 (s), 1103 (b), 842(s), 780 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 3.61 (dd, J=10.5, 5.7 Hz,1H), 3.54 (dd, J=10.5, 4.9 Hz, 1H), 3.40 (s, 3H), 3.18 (m, 1H), 1.42 (m,4H), 0.91 (app t, J=7.1 Hz, 3H), 0.89 (s, 9H), 0.05 (s, 6H); ¹³CNMR (125MHz, CDCl₃) δ 82.0, 65.5, 58.1, 33.8, 26.1, 18.8, 14.4, −2.7, −5.1,−5.2; high resolution mass spectrum (C₁, NH₃) m/z 233.4439 [(M)⁺; calcdfor C₁₂H₂₈O₂Si: 233.4441].

Alcohol (−)-3.S₂:

To a stirred solution of (−)-3.31 (0.12 g, 0.517 mmol) in freshlydistilled THF (10.3 mL) at 0° C. under argon was added dropwise,tetrabutylammonium fluoride (1.0 M/THF) (0.78 mL, 0.780 mmol). Afterstirring for one hour, the reaction was quenched via dropwise additionof saturated aqueous sodium chloride (5 mL) and allowed to warm to roomtemperature. The layers of the biphasic mixture were separated and theaqueous layer was extracted with ethyl acetate (7 mL, 3×). The combinedorganic layers were dried over MgSO₄, filtered and concentrated invacuo. Purification via silica gel chromatography (40% Et₂O/pentane)afforded alcohol (−)-3.S₂ (57.9 mg, 95%) as a colorless oil. [α]_(D)²⁰−32.7 (c 0.49, CHCl₃); IR (neat) 3246 (b), 2953 (m), 1463 (s), 1378(b), 1139 (s), 1095 (b), 1056 (s), 812 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃)δ 3.68 (dd, J=11.5, 3.3 Hz, 1H), 3.47 (dd, J=11.5, 6.5 Hz, 1H), 3.41 (s,3H), 3.26 (m, 2H), 1.92 (br s, 1H), 1.56 (m, 1H), 1.38 (m, 2H), 0.94(app t, J=7.3, 3H); ¹³CNMR (125 MHz, CDCl₃) δ 81.6, 64.2, 57.3, 32.7,18.8, 14.5; high resolution mass spectrum (C₁, NH₃) m/z 119.0991 [(M)⁺;calcd for C₆H₁₄O₂: 119.0994].

Aldehyde (−)-3.32:

To a stirred solution of (−)-3.S₂ (0.23 g, 1.94 mmol) in dichloromethane(98 mL) at 0° C. under argon was added, in one portion, solid sodiumbicarbonate (0.41 g, 4.9 mmol) followed by portion wise addition ofDess-Martin periodinane (4.17 g, 9.80 mmol). After ten minutes, thereaction was warmed to room temperature and stirred for two hours, atwhich point the reaction was quenched via dropwise addition of saturatedaqueous sodium bicarbonate (35 mL). The layers of the biphasic solutionwere separated and the aqueous layer extracted with dichloromethane (15mL, 3×). The combined organic extracts were dried over MgSO₄, filteredand concentrated in vacuo. Purification via silica gel chromatography,(10% Et₂O/pentane) afforded (−)-3.32 (0.21 g, 91%) as an amorphoussolid. [α]_(D) ²⁰−34.8 (c 0.52, CHCl₃); IR (neat) 2925 (m), 1737 (s),1458 (b), 1098 (b) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 9.65 (dd, J=1.9, 0.7Hz, 1H), 3.56 (ddd, J=6.2, 5.4, 1.9 Hz, 1H), 3.44 (d, J=0.8 Hz, 3H),1.63 (m, 2H), 1.43 (m, 2H), 0.93 (app t, J=7.4 Hz, 3H); ¹³CNMR (125 MHz,CDCl₃) δ 204.5, 86.0, 58.7, 32.3, 18.4, 14.3; high resolution massspectrum (CT, NH₃) m/z 117.0143 [(M); calcd for C₆H₁₂O₂: 117.0138].

Lactone (−)-3.33:

To a solution of chromium(II) chloride (1.41 g, 11.5 mmol) in freshlydistilled THF (4.5 mL) at room temperature under an argon atmosphere wasadded dropwise, anhydrous DMF (0.87 mL). The resultant brown solutionwas vigorously stirred for thirty minutes, at which point a solution ofaldehyde (−)-3.32 (0.13 g, 1.12 mmol) andtributyl(dibromomethyl)stannane (Bu₃SnCHBr₂) (1.14 g, 2.50 mmol) infreshly distilled THF (4.5 mL) were added dropwise via cannula. Thesolution was covered with aluminum foil to preclude exposure to light.Flame dried lithium iodide (0.59 g, 4.50 mmol) in freshly distilled THF(4.5 mL) was added dropwise via syringe and the reaction mixture wasstirred at room temperature. After twenty four hours, the reaction wasquenched via dropwise addition of water (5 mL). The layers of thebiphasic solution were separated and the aqueous layer was extractedwith diethyl ether (10 mL, 3×). The combined organic layers were washedwith water (5 mL), saturated aqueous sodium chloride (5 mL), dried overMgSO₄, filtered and concentrated in vacuo to afford a light green oil.Due to decomposition upon silica gel chromatography, 3.24 was carried oncrude (78%, 20:1, E:Z by ¹HNMR [C₆D₆] analysis of the crude isolate).

Vinyl stannane 3.24 (0.136 g, 0.34 mmol) and known vinyl iodide IX(Smith, et al. J. Am. Chem. Soc. 2001, 123, 10942) (0.041 g, 0.084 mmol)were combined in a round bottom flask, azeotroped from benzene (5 mL,3×) and dried under vacuum for thirty minutes. To the flask under anargon atmosphere were added, Ph₂PO₂NBu₄ (0.039 g, 0.084 mmol) andtris(dibenzylideneacetone)dipalladium-chloroform adduct[Pd₂(dba)₃.CHCl₃] (8.7 mg, 0.0084 mmol) followed by anhydrous DMF (0.85mL, sparged with argon, one hour). After four hours at room temperature,the reaction was purified directly via silica gel chromatography (20%EtOAc/hexanes) to afford (−)-3.33 (0.47 g, 89%) as a colorless oil.[α]_(D) ²⁰−12.0 (c 0.05, CHCl₃); IR (neat) 2941 (b), 2868 (s), 1748 (s),1460 (s), 1371 (b), 1240 (b), 1093 (b), 884 (s), 795 (s), 680 (s) cm⁻¹;¹HNMR (500 MHz, CDCl₃) δ 6.16 (d, J=15.7 Hz, 1H), 5.51 (dd, J=15.7, 7.8Hz, 1H), 5.44 (d, J=8.8 Hz, 1H), 4.79 (dd, J=8.8, 4.7 Hz, 1H), 4.23(ddd, J=8.5, 7.5, 3.4 Hz, 1H), 3.69 (m, 1H), 3.58 (app q, J=6.6 Hz, 1H),3.36 (d, J=0.9 Hz, 3H), 3.26 (d, J=0.8 Hz, 3H), 2.89 (dd, J=17.2, 5.8Hz, 1H), 2.40 (m, 2H), 1.81 (s, 3H), 1.59 (m, 2H), 1.43 (m, 1H), 1.31(m, 2H), 1.04 (m, 21H), 0.91 (app t, J=7.2 Hz, 3H); ¹³CNMR (125 MHz,CDCl₃) δ 169.8, 136.2, 136.1, 130.6, 130.0, 82.4, 80.4, 72.7, 70.3,56.5, 56.2, 37.9, 37.1, 29.8, 18.8, 18.1, 14.2, 13.8, 12.5; highresolution mass spectrum (ES⁺) m/z 491.3170 [(M+Na)⁺; calcd forC₂₆H₄₈O₅SiNa: 491.3168].

Mixed Methyl Ketal (−)-3.S₃:

To lactone (−)-3.33 (29.0 mg, 0.063 mmol) in a flame dried round bottomflask under argon at room temperature in freshly distilled THF (3.0 mL)was added oxazole 2.9 (0.12 g, 0.380 mmol) and the solution cooled to 0°C. iso-Propylmagnesium chloride (2.0 M/THF, 0.079 mL, 0.157 mmol) wasthen added dropwise over thirty minutes. After stirring for twentyminutes, another addition of iso-propylmagnesium chloride (2.0 M/THF,0.04 mL, 0.076 mmol) was introduced over twenty minutes. After a thirdaddition of iso-propylmagnesium chloride (0.04 mL, 0.076 mmol) andstirring for thirty minutes, the reaction was quenched via dropwiseaddition of saturated aqueous sodium bicarbonate (3 mL). The solutionwas warmed to room temperature, at which point the layers of thebiphasic mixture were separated and the aqueous layer was extracted withethyl acetate (5 mL, 3×). The combined organic extracts were dried overMgSO₄, filtered and concentrated in vacuo. The resultant pale yellow oilwas then dissolved in anhydrous methanol (7.3 mL) followed by theaddition of p-TsOHOH₂O (7 mg, 0.038 mmol) under an argon atmosphere.After stirring for twenty hours at room temperature, the reaction wasquenched via dropwise addition of aqueous saturated sodium bicarbonate(8 mL). The biphasic mixture was extracted with ethyl acetate (5 mL, 3×)and the combined organic extracts were dried over MgSO₄, filtered andconcentrated in vacuo. Purification via silica gel chromatography (20%EtOAc/hexanes) afforded (−)-3.S₃ (21.1 mg, 47%) over the two steps as acolorless oil. [α]_(D) ²⁰−13.2 (c 0.61, CHCl₃); IR (neat) 2935 (b), 2867(s), 1593 (s), 1433 (s), 1375 (b), 1224 (s), 1137 (s), 1098 (b), 860 (b)cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.60 (s, 1H), 6.15 (d, J=15.7 Hz, 1H),5.47 (dd, J=15.7, 7.9 Hz, 1H), 5.38 (d, J=8.9, Hz, 1H), 4.64 (dd, J=8.9,6.2 Hz, 1H), 3.56 (m, 3H), 3.31 (s, 3H), 3.30 (s, 3H), 3.27 (s, 3H),3.26 (d, J=15.5 Hz, 1H), 2.99 (d, J=14.9 Hz, 1H), 2.17 (dddd, J=12.6,4.6, 4.6, 1.5 Hz, 1H), 1.99 (dd, J=12.2, 4.3, Hz, 1H), 1.77 (d, J=0.9Hz, 3H), 1.62 (m, 1H), 1.44 (m, 1H), 1.34 (m, 3H), 1.07 (m, 22H), 0.92(app t, J=7.3 Hz, 3H); ¹³CNMR (125 MHz, CDCl₃) δ 159.0, 145.0, 136.6,134.6, 132.3, 129.8, 127.1, 99.9, 82.6, 74.4, 73.6, 71.9, 56.4, 55.8,48.1, 39.4, 37.9, 36.2, 32.3, 18.8, 18.2, 18.1, 14.2, 13.8, 12.6; highresolution mass spectrum (ES⁺) m/z 736.3152 [(M+Na)⁺; calcd forC₃₂H₅₄NO₉SSiNa: 736.3137].

C(45-46)-Alkyl Stannane Sidechain (−)-3.20:

Oxazole triflate (−)-3.S3 (42 mg, 0.059 mmol) was combined withhexamethylditin (0.017 mL, 0.082 mmol) in a sealed tube (100 mL),azeotroped from benzene (5 mL, 3×) and dried under vacuum for one hour.To the sealed tube in a glove bag under an argon atmosphere was addedflame dried lithium chloride (40 mg, 0.940 mmol),tetrakis(triphenylphosphine)palladium [Pd(PPh₃)₄] (10 mg, 0.008 mmol)and anhydrous dioxane (0.60 mL, freeze pump thawed, 3×). The tube wassealed and the reaction vessel heated to 90° C. behind a blast shield.After twelve hours, the reaction was cooled to room temperature andpurified directly via silica gel chromatography (15% EtOAc/hexanes) toafford (−)-3.20 (27.5 mg, 64%) as a colorless oil. [α]_(D) ²⁰−14.6 (c0.57, CH₂Cl₂); IR (neat) 2930 (b), 2870 (s), 1462 (s), 1378 (b), 1087(b), 879 (s), 775 (b); ¹HNMR (500 MHz, C₆D₆) δ 7.21 (s, 1H), 6.23 (d,J=15.7 Hz, 1H), 5.56 (dd, J=15.7, 7.7 Hz, 1H), 5.53 (d, J=8.4 Hz, 1H),4.73 (dd, J=8.8, 6.3 Hz, 1H), 3.74 (m, 1H), 3.67 (m, 1H), 3.52 (app q,J=6.8 Hz, 1H), 3.46 (d, J=14.9 Hz, 1H), 3.43 (s, 3H), 3.17 (s, 3H), 3.06(s, 3H), 3.05 (d, J=14.7 Hz, 1H), 2.57 (dddd, J=12.6, 4.5, 4.4, 1.4 Hz,1H), 2.14 (dd, J=12.2, 2.2 Hz, 1H), 1.73 (s, 3H), 1.68 (app q, J=6.5 Hz,1H), 1.47 (m, 2H), 1.35 (m, 3H), 1.14 (m, 21H), 0.88 (app t, J=7.3 Hz,3H), 0.24 (s, 9H); ¹³CNMR (125 MHz, C₆D₆) δ 161.5, 145.4, 136.7, 135.1,133.1, 130.9, 100.9, 82.8, 74.7, 74.2, 72.9, 56.5, 55.6, 48.3, 40.6,38.8, 36.4, 33.2, 19.4, 18.7, 18.6, 14.6, 14.1, 13.2, −9.3;high-resolution mass spectrum (ES⁺) m/z 752.3370 [(M+Na)⁺; calcd forC₃₄H₆₃NO₆SiSnNa: 752.3345].

Terminal Alkyne Sidechain (−)-3.28:

To a solution of oxazole triflate (−)-2.S5 (43 mg, 0.055 mmol) under anargon atmosphere in freshly distilled THF (1 mL), absolute ethanol (1mL), and water (1 mL) was added 2,6-lutidine (0.086 ml) at roomtemperature. After stirring for five minutes, silver nitrate (93.0 mg,0.550 mmol) was added as one portion. After fifteen hours, the reactionwas quenched via dropwise addition of 1N potassium dihydrogenphosphate(KH₂PO₄) (5 mL). After stirring for five minutes at room temperature,the yellow biphasic mixture was poured into saturated aqueous sodiumchloride (10 mL) and extracted with ethyl acetate (10 mL, 3×). Thecombined organic extracts were dried over MgSO₄, filtered andconcentrated in vacuo. Purification via silica gel chromatography (30%EtOAc/hexanes) afforded terminal alkyne sidechain (−)-3.28 (35.5 mg,91%) as a pale yellow oil. [α]_(D) ²⁰−31.1 (c 0.09, CHCl₃); IR (neat)2941 (b), 2868 (s), 1591 (s), 1434 (s), 1230 (s), 1141 (s), 1093 (s),1015 (s), 858 (s), 800 (b); ¹HNMR (500 MHz, CDCl₃) δ 7.60 (s, 1H), 6.25(d, J=15.7 Hz, 1H), 5.57 (dd, J=15.6, 7.7 Hz, 1H), 5.43 (d, J=8.9 Hz,1H), 4.61 (dd, J=8.9, 6.3 Hz, 1H), 3.79 (app q, J=6.0 Hz, 1H), 3.56 (m,2H), 3.32 (s, 3H), 3.31 (s, 3H), 3.30 (s, 3H), 3.25 (d, J=14.9 Hz, 1H),2.98 (d, J=14.9 Hz, 1H), 2.49 (m, 2H), 2.17 (dddd, J=12.6, 4.6, 4.5,1.7, Hz, 1H), 1.99 (app t, J=2.6 Hz, 1H), 1.78 (d, J=1.1 Hz, 3H), 1.37(dd, J=12.6, 11.1 Hz, 1H), 1.06 (m, 23H); ¹³CNMR (125 MHz, CDCl₃) δ158.9, 144.9, 137.7, 134.4, 133.2, 127.5, 127.1, 99.9, 80.8, 80.6, 74.3,73.5, 71.8, 70.1, 56.8, 55.8, 48.2, 39.3, 36.1, 32.2, 25.9, 18.2, 18.1,13.8, 12.6; high resolution mass spectrum (ES⁺) m/z 732.2795 [(M+Na)⁺;calcd for C₃₂H₅₀F₃NO₉SSiNa: 732.2826].

C(45-46)-Alkenyl Stannane Sidechain (−)-3.19:

To a stirring solution of alkyne (−)-3.28 (37.0 mg, 0.052 mmol) inacetone (3.5 mL) and 1-hexene (3.5 mL) at room temperature under anargon atmosphere were added quinoline (0.061 ml, 0.520 mmol), andLindlar's catalyst (5% Pd/CaCO₃, poisoned with Pb) (20 mg, 0.010 mmol).Under vigorous stirring, the reaction vessel was fitted with a hydrogenballoon and stirred at room temperature. After three hours, the reactionwas quenched with 1N hydrogen chloride solution (5 mL) and allowed tostir for one minute. The biphasic solution was filtered through a pad ofCelite, and washed with acetone (10 mL, 3×). The layers of the biphasicmixture were separated and the aqueous layer was extracted with ethylacetate (10 mL, 3×). The combined organic extracts were dried overMgSO₄, filtered and concentrated under reduced pressure. CrudeC(45-46)-alkene 3.27 (27 mg, 0.038 mmol) was then combined withhexamethylditin (0.011 mL, 0.053 mmol) in a sealed tube (100 mL),azeotroped from benzene (5 mL, 3×) and dried under vacuum for one hour.In a glove bag under an inert argon atmosphere was added flame driedlithium chloride (25 mg, 0.600 mmol),tetrakis(triphenylphosphine)palladium [Pd(PPh₃)₄] (6 mg, 0.006 mmol) anddioxane (0.5 mL, freeze pump thawed, 3×). The tube was sealed and heatedto 90° C. behind a blast shield. After fifteen hours, the reaction wascooled to room temperature and the reaction mixture was introduceddirectly onto a silica gel column, (15% EtOAc/hexanes) to afford(−)-3.19 (26.4 mg, 69%, 2-steps) as a colorless oil. [α]_(D) ²⁰−12.6 (c0.92, CH₂Cl₂); IR (neat) 2935 (s), 2867 (s), 1559 (s), 1457 (s), 1300(b), 1093 (s), 966 (s), 882 (s), 775 (b) cm⁻¹; ¹HNMR (500 MHz, C₆D₆) δ7.21 (s, 1H), 6.21 (d, J=15.7 Hz, 1H), 5.90 (m, 1H), 5.54 (dd, J=15.7,7.7 Hz, 1H), 5.51 (d, J=7.2 Hz, 1H), 5.06 (s, 1H), 5.04 (d, J=2.0 Hz,1H), 4.72 (dd, J=8.8, 6.3 Hz, 1H), 3.73 (dd, J=10.2, 6.2 Hz, 1H), 3.67(m, 1H), 3.55 (dd, J=13.6, 6.5 Hz, 1H), 3.44 (d, J=18.2 Hz, 1H), 3.42(s, 3H), 3.13 (s, 3H), 3.05 (s, 3H), 3.04 (d, J=12.7 Hz, 1H), 2.56 (dd,J=12.7, 3.0 Hz, 1H), 2.43 (m, 1H), 2.28 (m, 1H), 2.12 (d, J=10.0 Hz,1H), 1.71 (s, 3H), 1.67 (app t, J=12.6 Hz, 1H), 1.30 (app q, J=11.9 Hz,1H), 1.13 (m, 21H), 0.24 (s, 9H); ¹³CNMR (125 MHz, C₆D₆) δ 161.7, 145.6,138.6, 137.2, 135.7, 135.1, 133.5, 130.2, 117.3, 101.1, 82.8, 74.9,74.4, 73.1, 56.6, 55.8, 48.5, 41.3, 40.7, 36.6, 33.4, 18.8, 18.7, 14.3,13.4; high resolution mass spectrum (ES⁺) m/z 750.3220 [(M+Na)⁺; calcdfor C₃₄H₆INO₆SiSnNa: 750.3213].

C(45-46)-E-Chloroalkene (−)-S₅:

To a solution of terminal alkyne (−)-3.28 (32 mg, 0.045 mmol) inanhydrous benzene (1.3 mL) at room temperature under an argon atmospherewas added 2,2′-azobis(2-methylpropionitrile) (AIBN) (1 mg, 0.009 mmol)in one portion, followed by the dropwise addition of tri-n-butyltinhydride (0.024 ml, 0.09 mmol) and the reaction was heated to 85° C.After four hours, the reaction was cooled to room temperature, dilutedwith dichloromethane (3 mL) and concentrated in vacuo. The resultantcrude vinyl stannane (26 mg, 0.026 mmol), as a colorless oil, was thendissolved in freshly distilled THF (1 mL). Copper(II) chloride (8 mg,0.057 mmol) was added in one portion and the resultant yellow solutionwas stirred at room temperature under an argon atmosphere. After fifteenhours, the reaction was quenched via dropwise addition of saturatedaqueous sodium bicarbonate (5 mL). The layers of the resultant biphasicmixture were separated and the aqueous layer was extracted withdichloromethane (5 mL, 4×). The combined organic extracts were driedover MgSO₄, filtered and concentrated in vacuo. Purification via silicagel chromatography, (25% EtOAc/hexanes) afforded C(45-46)-E-chloroalkene(−)-3.29 (21.5 mg, 64%, 13:1, E:Z, 2 steps) as a colorless oil. [α]_(D)²⁰−31.3 (c 0.41, CHCl₃); IR (neat) 2942 (b), 2864 (s), 1594 (s), 1432(s), 1231 (s), 1138 (s), 1094 (b), 854 (b); ¹HNMR (500 MHz, CDCl₃) δ7.60 (s, 1H), 6.17 (d, J=15.7 Hz, 1H), 6.00 (d, J=13.3 Hz, 1H), 5.89 (m,1H), 5.45 (dd, J=15.7, 7.8 Hz, 1H), 5.42 (d, J=9.4 Hz, 1H), 4.60 (dd,J=8.8, 6.2 Hz, 1H), 3.64 (app q, J=6.5 Hz, 1H), 3.56 (m, 2H), 3.31 (s,3H), 3.30 (s, 3H), 3.27 (s, 3H), 3.25 (d, J=14.9 Hz, 1H), 2.98 (d,J=14.9 Hz, 1H), 2.37 (m, 1H), 2.27 (m, 1H), 2.17 (dd, J=12.6, 3.5 Hz,1H), 1.99 (ddd, J=10.0, 4.2, 2.1 Hz, 1H), 1.76 (s, 3H), 1.38 (d, J=12.3Hz, 1H), 1.36 (d, J=11.4 Hz, 1H), 1.06 (m, 21H); ¹³CNMR (125 MHz, CDCl₃)δ 159.0, 145.0, 137.4, 134.3, 133.1, 129.8, 128.3, 127.1, 119.1, 99.9,81.7, 74.3, 73.5, 71.8, 56.5, 55.7, 48.1, 39.3, 37.4, 36.1, 32.2, 18.2,18.1, 13.8, 12.6; high resolution mass spectrum (ES⁺) m/z 769.3469[(M+Na)⁺; calcd for C₃₂H₅₁F₃NO₉SSiClNa: 769.3474].

C(45-46)-E-Chloroalkenyl Stannane Sidechain (−)-3.21:

C(45-46)-E-chloroalkene (−)-3.29 (0.42 g, 0.059 mmol) was combined withhexamethylditin (0.017 mL, 0.082 mmol) in a sealed tube (100 mL),azeotroped from benzene (5 mL, 3×) and dried for one hour under vacuum.In a glove bag under an inert argon atmosphere was added flame driedlithium chloride (39 mg, 0.941 mmol) followed bytetrakis(triphenylphosphine)palladium [Pd(PPh₃)₄] (10 mg, 0.009 mmol)and dioxane (0.6 mL, freeze pump thawed, 3×). The tube was sealed andthe reaction mixture heated to 80° C. behind a blast shield. Aftertwelve hours, the reaction was cooled to room temperature and introduceddirectly onto a silica gel column, (15% EtOAc/hexanes) to affordC(45-46)-E-chloroalkene stannane sidechain (−)-3.21 (30.5 mg, 68%) as acolorless oil. [α]_(D) ²⁰−28.4 (c 0.32, CH₂Cl₂); IR (neat) 2940 (s),2863 (s), 1556 (s), 1460 (s), 1378 (b), 1244 (s), 1095 (b), 990 (s), 883(s), 773 (s), 681 (s); ¹HNMR (500 MHz, C₆D₆) δ 7.21 (s, 1H) 6.12 (d,J=15.7 Hz, 1H), 5.90 (ddd, J=13.3, 7.5, 7.4 Hz, 1H), 5.69 (d, J=13.3 Hz,1H), 5.51 (d, J=8.9 Hz, 1H), 5.38 (dd, J=15.7, 7.8 Hz, 1H), 4.72 (dd,J=8.8, 6.3 Hz, 1H), 3.74 (m, 1H), 3.66 (m, 1H), 3.45 (d, J=14.9 Hz, 1H),3.43 (s, 3H), 3.35 (app q, J=6.4 Hz, 1H), 3.06 (s, 3H), 3.03 (s, 3H),2.56 (dd, J=12.7, 3.0 Hz, 1H), 2.12 (m, 2H), 1.99 (app q, J=6.1 Hz, 1H),1.68 (s, 3H), 1.30 (dd, J=23.6, 11.9 Hz, 2H), 1.14 (m, 22H), 0.24 (s,9H); ¹³CNMR (125 MHz, C₆D₆) δ 161.5, 145.4, 137.5, 134.7, 133.8, 130.5,129.3, 119.5, 100.9, 81.9, 74.7, 74.2, 72.8, 56.4, 55.6, 48.3, 40.5,37.8, 36.4, 33.2, 18.7, 18.6, 14.1, 13.2, −9.3; high resolution massspectrum (ES⁺) m/z 784.2787 [(M+Na)⁺; calcd for C₃₄H₆₀ClNO₆SiSnNa:784.2645].

Protected C(45-46)-TMS-Alkynyl-Phorboxazole (+)-3.35:

Vinyliodide macrocycle (+)-2.5 (13.8 mg, 0.017 mmol) andC(45-46)-TMS-alkyne stannane sidechain (−)-2.90 (21.0 mg, 0.026 mmol)were combined in a flame dried round bottom flask (5 mL), azeotropedfrom benzene (2 mL, 3×) and dried under vacuum for two hours. To theflask under an argon atmosphere was added tris(dibenzylideneacetone)dipalladium-chloroform adduct [Pd₂(dba)₃.CHCl₃] (3.6 mg, 0.003 mmol),triphenylarsine (AsPh₃) (6.4 mg, 0.021 mmol) and Ph₂PO₂NBU₄. (12 mg,0.026 mmol) followed by introduction of DMF (0.17 mL, sparged withargon, thirty minutes) and diisopropylethylamine (0.003 mL, 0.017 mmol).After the reaction was allowed to stir for sixteen hours at roomtemperature, the light brown reaction mixture was introduced directlyonto a silica gel column, (20% EtOAc/hexanes→30% EtOAc/hexanes) toafford protected C(45-46)-TMS-alkynyl-phorboxazole (+)-3.35 (14.9 mg,68%) as a light yellow oil. [α]_(D) ²⁰+1.36 (c 0.22, CHCl₃); IR (neat)2925.8 (b), 1718 (s), 1456 (b), 1250 (s), 1187 (s), 1091 (s), 1053 (b),840 (s) cm⁻¹; ¹HNMR (500 MHz, C₆D₆) δ 6.96 (s, 1H), 6.90 (m, 1H), 6.37(s, 1H), 6.32 (d, J=15.7 Hz, 1H), 6.20 (d, J=15.9 Hz, 1H), 5.79 (dd,J=11.2, 2.3 Hz, 1H), 5.69 (dd, J=15.7, 7.3 Hz, 1H), 5.57 (d, J=8.9 Hz,1H), 5.47 (ddd, J=10.7, 10.5, 2.9 Hz, 1H), 5.18 (s, 1H), 4.96 (dd,J=11.3, 2.0 Hz, 1H), 4.77 (m, 2H), 4.62 (dd, J=11.2, 4.4 Hz, 1H), 4.39(m, 1H), 4.25 (app t, J=10.4 Hz, 1H), 4.08 (m, 1H), 4.03 (d, J=2.6 Hz,1H), 3.95 (m, 1H), 3.76 (m, 1H), 3.69 (app t, J=6.9 Hz, 1H), 3.68 (m,1H), 3.52 (dd, J=9.4, 4.6 Hz, 1H), 3.45 (d, J=10.1 Hz, 1H), 3.41 (s,3H), 3.34 (d, J=14.7 Hz, 1H), 3.28 (app t, J=4.8 Hz, 1H), 3.23 (app t,J=5.0 Hz, 1H), 3.09 (s, 3H), 3.08 (s, 3H), 3.04 (d, J=11.4 Hz, 1H), 2.95(d, J=14.8 Hz, 1H), 2.66 (app t, J=6.3 Hz, 1H), 2.60 (m, 1H), 2.58 (dd,J=16.7, 5.7 Hz, 1H), 2.44 (dd, J=16.7, 6.8 Hz, 1H), 2.42 (m, 2H), 2.37(dd, J=12.8, 5.5 Hz, 1H), 2.17 (dd, J=10.0, 7.7 Hz, 1H), 2.10 (m, 1H),2.09 (d, J=0.6 Hz, 3H), 2.02 (d, J=11.8 Hz, 1H), 1.98 (d, J=13.0 Hz,1H), 1.77 (d, J=0.8 Hz, 3H), 1.65 (m, 3H), 1.49 (d, J=13.2 Hz, 1H), 1.35(m, 3H), 1.17 (m, 22H), 1.05 (d, J=6.9 Hz, 3H), 0.94 (s, 9H), 0.77 (d,J=6.5 Hz, 3H), 0.24 (s, 9H), 0.03 (s, 3H), 0.01 (s, 3H); ¹³CNMR (125MHz, C₆D₆) δ 165.8, 161.7, 160.0, 145.5, 143.8, 143.0, 139.2, 138.2,137.3, 136.8, 135.0, 134.4, 133.8, 133.5, 121.4, 120.1, 119.5, 110.5,104.6, 100.8, 90.0, 86.8, 81.0, 80.2, 78.7, 74.7, 74.1, 73.7, 72.7,69.9, 69.3, 67.7, 65.9, 56.7, 55.6, 48.3, 42.4, 40.5, 40.4, 40.0, 37.9,36.4, 36.3, 34.9, 33.1, 32.4, 31.2, 30.5, 27.9, 26.3, 18.7, 18.6, 14.6,14.1, 13.7, 13.2, 6.6, 1.7, 0.6, −4.5, −4.4; high-resolution massspectrum (ES⁺) m/z 1321.7641 [(M+Na)⁺; calcd for C₇₂H₁₁₄N₂O₁₃Si₃Na:1321.7626].

Protected C(45-46)-Alkyl-Phorboxazole (+)-3.37:

To a flame dried round bottom flask (5 mL), vinyl iodide macrocycle(+)-2.5 (10.7 mg, 0.013 mmol) was combined with the C(45-46)-alkyl sidechain (−)-3.20 (14.7 mg, 0.020 mmol), azeotroped from benzene (3 mL, 3×)and dried under vacuum. After two hours, under an argon atmosphere,tris(dibenzylideneacetone)dipalladium-chloroform adduct[Pd₂(dba)₃.CHCl₃] (2.8 mg, 0.0027 mmol), triphenylarsine (AsPh₃) (4.9mg, 0.016 mmol) and Ph₂PO₂NBu₄ (9.3 mg, 0.020 mmol) were added followedby anhydrous DMF (0.14 mL, sparged with argon, one hour) anddiisopropylethylamine (0.002 mL, 0.014 mmol). After two minutes, theblack solution turned light brown and was stirred at room temperature.After sixteen hours, the light brown reaction mixture was purifieddirectly via silica gel chromatography, (25% EtOAc/hexanes) to affordprotected C(45-46)-alkyl-phorboxazole (+)-3.37 (13.5 mg, 82%) as an offwhite foam. [α]_(D) ²⁰−7.3 (c 0.65, CHCl₃); IR (neat) 2930 (s), 2865(s), 1717 (s), 1459 (b), 1382 (b), 1188 (s), 1095 (s), 1055 (b), 881(s), 837 (s); ¹HNMR (500 MHz, C₆D₆) δ 7.14 (s, 1H), 6.95 (s, 1H), 6.89(m, 1H), 6.36 (s, 1H), 6.24 (d, J=15.7 Hz, 1H), 6.18 (d, J=15.9 Hz, 1H),5.78 (dd, J=11.1, 2.5 Hz, 1H), 5.57 (dd, J=11.1, 2.5 Hz, 1H), 5.54 (d,J=9.1 Hz, 1H), 5.43 (ddd, J=10.7, 10.7, 2.6 Hz, 1H), 5.19 (s, 1H), 4.95(d, J=11.2 Hz, 1H), 4.74 (m, 2H), 4.61 (dd, J=15.5, 4.3 Hz, 1H), 4.39(br s, 1H), 4.24 (app t, J=10.3 Hz, 1H), 4.07 (m, 1H), 4.01 (d, J=2.8Hz, 1H), 3.96 (m, 1H), 3.77 (dd, J=6.2, 1.7 Hz, 1H), 3.71 (m, 1H), 3.52(dd, J=12.7, 6.8 Hz, 1H), 3.43 (d, J=12.6 Hz, 1H), 3.41 (s, 3H), 3.39(m, 2H), 3.35 (d, J=14.8 Hz, 1H), 3.17 (s, 3H), 3.06 (s, 3H), 2.94 (d,J=14.8 Hz, 1H), 2.65 (app t, J=5.7 Hz, 1H), 2.57 (dd, J=12.7, 3.5 Hz,1H), 2.39 (m, 4H), 2.17 (dd, J=10.1, 7.9 Hz, 1H), 2.08 (s, 3H), 2.04 (m,2H), 1.97 (app t, J=14.2 Hz, 1H), 1.74 (s, 3H), 1.65 (m, 3H), 1.48 (m,3H), 1.37 (m, 4H), 1.15 (m, 23H), 1.04 (d, J=6.8 Hz, 3H), 0.92 (s, 9H),0.89 (app t, J=7.3 Hz, 3H), 0.76 (d, J=6.4 Hz, 3H), 0.01 (s, 3H), −0.01(s, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 165.9, 161.9, 160.2, 145.8, 144.0,143.2, 139.4, 138.4, 137.0, 136.9, 135.3, 134.5, 134.0, 133.2, 131.1,121.6, 120.4, 119.7, 110.7, 101.0, 90.2, 83.0, 80.4, 78.9, 74.9, 74.4,73.9, 72.9, 70.1, 69.4, 67.9, 66.1, 56.7, 55.8, 48.5, 42.6, 40.7, 40.6,40.2, 39.0, 38.1, 36.5, 35.1, 33.4, 33.3, 32.6, 31.3, 30.7, 26.6, 26.5,19.6, 18.9, 18.7, 14.8, 14.3, 13.9, 13.3, 6.8, −4.2, −4.3; highresolution mass spectrum (ES⁺) m/z 1253.7355 [(M+Na)⁺; calcd forC₆₉H₁₁₀N₂O₁₃Si₂Na: 1253.7442].

Protected C(45-46)-Alkenyl-Phorboxazole (+)-3.36:

In a flame dried round bottom flask (5 mL), vinyl iodide macrocycle(+)-2.5 (7.0 mg, 0.009 mmol) and C(45-46)-alkenyl sidechain (−)-3.19(9.6 mg, 0.013 mmol) were combined, azeotroped from benzene (3 mL, 3×)and dried under reduced pressure. After one hour, under an inert argonatmosphere, tris(dibenzylideneacetone)dipalladium-chloroform adduct[Pd₂(dba)₃.CHCl₃] (1.8 mg, 0.0017 mmol), triphenylarsine (AsPh₃) (3.2mg, 0.011 mmol) and Ph₂PO₂NBu₄ (6.1 mg, 0.013 mmol) were added followedby anhydrous DMF (0.1 mL, sparged with argon, one hour), anddiisopropylethylamine (0.001 mL, 0.009 mmol). After one minute, theblack solution turned light brown and was stirred at room temperature.After sixteen hours, the reaction mixture was purified directly viasilica gel chromatography, (20% EtOAc/hexanes) to afford protectedC(45-46)-alkenyl-phorboxazole (+)-3.36 (8.4 mg, 77%) as an off whitefoam. [α]_(D) ²⁰+7.4 (c 0.17, CHCl₃); IR (neat) 2989 (b), 2865 (s), 1721(s), 1646 (b), 1463 (b), 1384 (b), 1252 (b), 1187 (s), 1098 (s), 1061(b) cm⁻¹; ¹HNMR (500 MHz, C₆D₆) δ 7.12 (s, 1H), 6.95 (s, 1H), 6.88 (m,1H), 6.35 (s, 1H), 6.22 (d, J=16.1 Hz, 1H), 6.19 (d, J=17.4 Hz, 1H),5.91 (m, 1H), 5.78 (d, J=11.2 Hz, 1H), 5.56 (dd, J=15.7, 7.6 Hz, 1H),5.53 (d, J=7.8 Hz, 1H), 5.45 (app t, J=10.5 Hz, 1H), 5.17 (s, 1H), 5.06(d, J=12.2 Hz, 1H), 4.94 (d, J=10.1 Hz, 1H), 4.74 (s, 1H), 4.61 (dd,J=11.2, 4.2 Hz, 1H), 4.38 (br s, 1H), 4.25 (app t, J=10.6 Hz, 1H), 4.06(br s, 1H), 4.02 (s, 1H), 3.94 (m, 1H), 3.75 (m, 1H), 3.69 (m, 1H), 3.57(app q, J=6.6 Hz, 1H), 3.44 (d, J=10.0 Hz, 1H), 3.41 (s, 3H), 3.34 (d,J=14.8 Hz, 1H), 3.14 (s, 3H), 3.07 (s, 3H), 3.06 (m, 1H), 2.95 (d,J=14.8 Hz, 1H), 2.65 (br s, 1H), 2.56 (d, J=12.4 Hz, 1H), 2.41 (m, 5H),2.30 (m, 2H), 2.16 (d, J=10.1 Hz, 2H), 2.08 (s, 3H), 1.74 (s, 3H), 1.64(m, 4H), 1.48 (d, J=13.6 Hz, 1H), 1.34 (m, 6H), 1.17 (m, 22H), 1.04 (d,J=6.8 Hz, 3H), 0.93 (s, 9H), 0.76 (d, J=6.4 Hz, 3H), 0.01 (s, 3H), −0.01(s, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 165.8, 161.7, 160.0, 145.5, 143.8,143.0, 139.2, 138.2, 136.9, 136.8, 135.5, 135.0, 134.5, 133.8, 133.2,130.1, 121.4, 120.1, 119.5, 117.2, 110.5, 100.9, 90.0, 82.6, 80.3, 78.8,74.7, 74.2, 73.8, 72.8, 69.9, 69.3, 67.7, 65.9, 56.4, 55.6, 48.3, 42.4,41.1, 40.5, 40.5, 40.0, 37.9, 36.4, 36.3, 34.9, 33.1, 32.4, 31.2, 30.5,26.3, 18.7, 18.6, 14.6, 14.1, 13.7, 13.2, 6.6, −4.4, −4.5; highresolution mass spectrum (ES⁺) m/z 1251.7268 [(M+Na)⁺; calcd forC₆₉H₁₀₈N₂O₁₃Si₂Na: 1251.7286].

Protected C(45-46)-E-Chloroalkenyl-Phorboxazole (+)-3.38:

In a round bottom flask (5 mL), vinyl iodide macrocycle (+)-2.5 (11.4mg, 0.014 mmol) and C(45-46)-E-chloroalkene side chain (−)-3.21 (16.4mg, 0.021 mmol) were combined, azeotroped from benzene (3 mL, 3×) anddried under vacuum. After one hour, under an inert argon atmosphere,tris(dibenzylideneacetone)dipalladium-chloroform adduct[Pd₂(dba)₃.CHCl₃] (2.9 mg, 0.0028 mmol), triphenylarsine (AsPh₃) (5.3mg, 0.017 mmol) and Ph₂PO₂NBu₄ (9.9 mg, 0.021 mmol) were added followedby anhydrous DMF (0.14 mL, sparged with argon, one hour), anddiisopropylethylamine (0.002 mL, 0.014 mmol). After one minute, theblack solution turned light brown and was allowed to stir at roomtemperature. After seventeen hours, the light brown solution waspurified directly via silica gel chromatography (20% EtOAc/hexanes→25%EtOAc/hexanes) to afford protected C(45-46)-E-chloroalkenyl-phorboxazole(+)-3.38 (15.8 mg, 87%) as an off white foam. [α]_(D) ²⁰+14.3 (c 0.37,CHCl₃); IR (neat) 2933 (s), 2866 (s), 1716 (s), 1644 (b), 1461 (b), 1370(b), 1254 (s), 1187 (s), 1153 (s), 1096 (s), 1043 (b), 879 (s), 836 (s),807 (b) cm⁻¹; ¹HNMR (500 MHz, C₆D₆) δ 7.15 (s, 1H), 6.96 (s, 1H), 6.87(m, 1H), 6.35 (s, 1H), 6.19 (d, J=15.8 Hz, 1H), 6.14 (d, J=15.8 Hz, 1H),5.91 (m, 1H), 5.79 (dd, J=11.5, 2.9 Hz, 1H), 5.70 (d, J=13.3 Hz, 1H),5.53 (d, J=8.6 Hz, 1H), 5.45 (ddd, J=10.6, 10.6, 2.8 Hz, 1H), 5.41 (dd,J=15.7, 7.7 Hz, 1H), 5.17 (s, 1H), 4.94 (d, J=11.2 Hz, 1H), 4.73 (m,2H), 4.61 (dd, J=11.2, 4.4 Hz, 1H), 4.38 (br s, 1H), 4.24 (app t, J=10.7Hz, 1H), 4.06 (m, 1H), 4.02 (s, 1H), 3.94 (m, 1H), 3.77 (dd, J=6.1, 1.9Hz, 1H), 3.69 (m, 1H), 3.43 (d, J=10.0 Hz, 1H), 3.40 (s, 3H), 3.37 (d,J=6.7 Hz, 1H), 3.33 (d, J=14.8 Hz, 1H), 3.07 (s, 3H), 3.04 (s, 3H), 2.94(d, J=14.8 Hz, 1H), 2.64 (app t, J=5.8 Hz, 1H), 2.56 (dd, J=13.0, 4.4Hz, 1H), 2.39 (m, 3H), 2.13 (m, 2H), 2.08 (s, 3H), 2.00 (m, 3H), 1.70(s, 3H), 1.63 (m, 2H), 1.48 (d, J=13.2 Hz, 1H), 1.32 (m, 5H), 1.14 (m,25H), 1.03 (d, J=6.8 Hz, 3H), 0.92 (s, 9H), 0.76 (d, J=6.4 Hz, 3H), 0.01(s, 3H), −0.01 (s, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 165.9, 161.8, 160.2,145.8, 144.0, 143.2, 139.4, 138.4, 137.7, 136.9, 134.9, 134.5, 134.0,133.9, 130.7, 121.6, 120.4, 120.1, 119.7, 119.6, 110.7, 101.0, 90.2,82.1, 81.6, 80.4, 78.9, 74.9, 74.3, 73.9, 72.9, 70.1, 69.4, 67.9, 66.1,56.6, 55.8, 48.5, 42.6, 40.7, 40.6, 40.1, 38.1, 38.0, 36.5, 35.1, 33.3,32.6, 31.3, 30.7, 26.5, 18.9, 18.7, 14.8, 14.2, 13.9, 13.3, 6.8, −4.2,−4.3; high resolution mass spectrum (ES⁺) m/z 1285.7001 [(M+Na)⁺; calcdfor C₆₉H₁₀₇ClN₂O₁₃Si₂Na: 1285.6997].

Protected E-C(2-3)-C(45-46)-Alkynyl-Phorboxazole (+)-3.39:

In a flame dried round bottom flask (5 mL), E-C(2-3)-vinyl iodidemacrocycle (+)-2.5E (9.1 mg, 0.012 mmol) was combined withC(45-46)-TMS-alkynyl sidechain (−)-2.90 (13.7 mg, 0.017 mmol),azeotroped from benzene (2 mL, 3×) and dried under vacuum. After onehour, under an inert argon atmosphere,tris(dibenzylideneacetone)dipalladium-chloroform adduct[Pd₂(dba)₃.CHCl₃] (2.4 mg, 0.0023 mmol), triphenylarsine (AsPh₃) (4.2mg, 0.014 mmol) and Ph₂PO₂NBU₄ (8 mg, 0.017 mmol) were added followed byanhydrous DMF (0.12 mL, sparged with argon, one hour), anddiisopropylethylamine (0.002 ml, 0.011 mmol). After one minute, theblack solution turned light brown and the reaction was stirred at roomtemperature. After twenty hours, the reaction mixture was purifieddirectly via silica gel chromatography, (20% EtOAc/hexanes→30%EtOAc/hexanes) to afford protectedE-C(2-3)-C(45-46)-alkynyl-phorboxazole (+)-3.39 (9.7 mg, 66%) as an offwhite foam. [α]_(D) ²⁰+10.6 (c 0.31, CHCl₃); IR (neat) 2936 (b), 1718(s), 1653 (s), 1464 (b), 1351 (b), 1250 (s), 1151 (s), 1087 (s), 843 (s)cm⁻¹; ¹HNMR (500 MHz, C₆D₆) δ 7.13 (s, 1H), 6.92 (s, 1H), 6.89 (m, 1H),6.30 (d, J=15.7 Hz, 1H), 6.27 (s, 1H), 6.14 (d, J=16.0 Hz, 1H), 6.04 (d,J=15.2 Hz, 1H), 5.67 (dd, J=15.7, 7.3 Hz, 1H), 5.55 (d, J=8.9 Hz, 1H),5.08 (dd, J=10.8, 3.7 Hz, 1H), 4.95 (d, J=11.7 Hz, 1H), 4.75 (dd, J=8.7,6.1 Hz, 1H), 4.68 (s, 1H), 4.59 (s, 1H), 4.34 (br s, 1H), 4.00 (s, 1H),3.92 (br s, 1H), 3.75 (dd, J=11.7, 6.1 Hz, 1H), 3.68 (m, 2H), 3.42 (m,3H), 3.39 (s, 3H), 3.37 (d, J=9.8 Hz, 1H), 3.31 (d, J=14.9 Hz, 1H), 3.08(s, 3H), 3.07 (s, 3H), 2.92 (d, J=14.7 Hz, 1H), 2.83 (br s, 1H), 2.57(dd, J=16.7, 5.7 Hz, 1H), 2.56 (m, 1H), 2.47 (br s, 1H), 2.43 (dd,J=16.8, 6.8 Hz, 1H), 2.26 (m, 2H), 2.13 (m, 4H), 2.05 (s, 3H), 1.90 (d,J=12.6 Hz, 1H), 1.82 (d, J=13.6 Hz, 1H), 1.75 (s, 3H), 1.67 (m, 5H),1.33 (m, 4H), 1.15 (m, 21H), 0.96 (s, 9H), 0.84 (app t, J=7.4 Hz, 6H),0.23 (s, 9H), 0.00 (s, 3H), −0.01 (s 3H); ¹³CNMR (125 MHz, C₆D₆) δ167.5, 162.6, 160.1, 147.5, 143.8, 142.8, 139.5, 138.5, 137.5, 136.9,135.2, 134.5, 134.1, 133.8, 132.4, 130.1, 128.0, 124.3, 119.4, 119.1,111.4, 104.8, 101.0, 86.9, 81.2, 79.3, 77.3, 74.9, 74.3, 72.9, 71.0,66.4, 66.2, 59.2, 59.1, 56.9, 55.8, 48.4, 41.3, 40.6, 40.4, 38.8, 38.6,38.4, 36.5, 35.6, 33.2, 30.7, 28.0, 26.5, 24.6, 20.5, 19.0, 18.9, 18.8,14.7, 14.4, 14.3, 13.4, 0.84, −4.2; high resolution mass spectrum (ES⁺)m/z 1321.7463 [(M+Na)⁺; calcd for C₇₂H₁₁₄N₂O₁₃Si₃: 1321.7524].

Protected C(45-46)-Alkenyl-C(22-26)-Central Tetrahydropyran (+)-3.40:

To a flame dried round bottom flask (5 mL), C(22-26)-centraltetrahydropyran (+)-2.44 (12.1 mg, 0.016 mmol) was combined withC(45-46)-alkenyl sidechain (−)-3.19 (18.0 mg, 0.025 mmol), azeotropedfrom benzene (2 mL, 3×) and dried under vacuum. After one hour, under anargon atmosphere, tris(dibenzylideneacetone)dipalladium-chloroformadduct [Pd₂(dba)₃.CHCl₃] (3.4 mg, 0.0033 mmol), triphenylarsine (AsPh₃)(6.1 mg, 0.020 mmol) and Ph₂PO₂NBu₄ (11.4 mg, 0.025 mmol) were addedfollowed by anhydrous DMF (0.17 mL, sparged with argon, one hour), anddiisopropylethylamine (0.003 mL, 0.016 mmol). After one minute, theblack solution turned light brown and was allowed to stir at roomtemperature. After twenty hours, the reaction mixture was purifieddirectly via silica gel chromatography (10% EtOAc/hexanes→30%EtOAc/hexanes) to afford protected C(45-46)-alkenyl-C(22-26)-centraltetrahydropyran phorboxazole (+)-3.40 (12.9 mg, 69%) as a white foam.[α]_(D) ²⁰−2.3 (c 0.064, CHCl₃); IR (neat) 2940 (b), 2863 (s), 1585 (b),1513 (s), 1460 (s), 1383 (b), 1263 (b), 1100 (b), 801 (b), 701 (s) cm⁻¹;¹HNMR (500 MHz, C₆D₆) δ 7.81 (m, 3H), 7.28 (m, 2H), 7.25 (m, 2H), 7.14(s, 1H), 6.97 (d, J=1.8 Hz, 1H), 6.92 (dd, J=8.1, 1.8 Hz, 1H), 6.7 (d,J=8.1 Hz, 1H), 6.38 (s, 1H), 6.22 (d, J=15.7 Hz, 1H), 5.90 (m, 1H), 5.56(dd, J=15.7, 7.7 Hz, 1H), 5.53 (d, J=8.7 Hz, 1H), 5.07 (d, J=13.5, Hz,1H), 5.04 (d, J=13.9 Hz, 1H), 4.73 (dd, J=8.8, 6.2 Hz, 1H), 4.53 (d,J=11.4 Hz, 1H), 4.21 (d, J=11.4 Hz, 1H), 3.97 (m, 1H), 3.84 (m, 1H),3.75 (m, 2H), 3.69 (m, 1H), 3.56 (app q, J=6.5 Hz, 1H), 3.51 (s, 3H),3.47 (d, J=10.2 Hz, 1H), 3.45 (s, 3H), 3.40 (s, 3H), 3.34 (d, J=14.8 Hz,1H), 3.16 (dd, J=10.3, 4.6 Hz, 1H), 3.13 (s, 3H), 3.06 (s, 3H), 2.93 (d,J=14.8 Hz, 1H), 2.57 (dd, J=12.7, 3.2 Hz, 1H), 2.44 (m, 1H), 2.49 (m,1H), 2.15 (ddd, J=10.2, 4.4, 2.0 Hz, 1H), 2.07 (s, 3H), 1.99 (m, 3H),1.74 (m, 1H), 1.73 (s, 3H), 1.65 (dd, J=12.6, 11.0 Hz, 1H), 1.33 (m,2H), 1.21 (s, 9H), 1.15 (m, 23H), 1.10 (d, J=6.4 Hz, 3H), 0.96 (d, J=6.4Hz, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 160.1, 150.9, 150.4, 139.6, 139.2,137.1, 136.8, 136.6, 136.5, 135.6, 135.2, 134.9, 134.9, 133.4, 132.7,130.6, 130.3, 120.8, 119.3, 117.3, 113.0, 112.9, 101.1, 90.1, 84.4,82.8, 75.5, 74.9, 74.3, 72.9, 70.4, 61.8, 56.6, 56.3, 56.2, 55.8, 48.5,51.3, 40.7, 37.1, 36.5, 35.6, 34.4, 33.3, 27.7, 20.1, 18.9, 18.8, 14.8,14.5, 14.3, 13.3, 3.6; high resolution mass spectrum (ES⁺) m/z 1186.6799[(M+Na); calcd for C₆₈H₁INO₁₁Si₂Na: 1186.6809].

C(45-46)-Alkynyl-Phorboxazole (+)-3.11:

Fully protected C(45-46)-alkynyl-phorboxazole (+)-3.35 (3.8 mg, 0.003mmol) was introduced into a flame dried round bottom flask, azeotropedfrom benzene (2 mL, 3×) and dried under vacuum. After one hour,(+)-3.35, under an argon atmosphere was dissolved in freshly distilledTHF (0.7 mL) and cooled to 0° C. After five minutes, tetrabutylammoniumfluoride (1.0 M/THF) (0.009 mL, 0.009 mmol) was added dropwise. Afterone hour, the reaction was quenched via dropwise addition of saturatedaqueous sodium chloride (1 mL) and allowed to stir for thirty seconds.The layers of the biphasic mixture were separated and the aqueous layerextracted with ethyl acetate (4 mL, 4×). The combined organic extractswere dried over MgSO₄, filtered and concentrated under reduced pressure.The resultant crude amorphous solid, under an inert argon atmosphere wasthen dissolved in freshly distilled THF (2.1 mL) followed by dropwiseaddition of 6% hydrogen chloride solution (0.82 mL). After thirty sixhours at room temperature, the reaction was cooled to 0° C., poured intosaturated aqueous sodium bicarbonate (3 mL), extracted withdichloromethane (3 mL, 3×) followed by extraction with ethyl acetate (3mL, 2×). The combined organic extracts were dried over MgSO₄, filteredand concentrated under reduced pressure. Purification via silica gelchromatography, (100% EtOAc→10% CH₃OH/EtOAc) affordedC(45-46)-alkynyl-phorboxazole (+)-3.11 (1.7 mg, 64%) as a whiteamorphous solid. [α]_(D) ²⁰+64.1 (c 0.64, CH₂Cl₂); IR (neat) 3431 (b),2920 (s), 1643 (b), 1189 (s), 1091 (s); ¹HNMR (500 MHz, C₆D₆) δ 7.03 (s,1H), 6.90 (s, 1H), 6.86 (m, 1H), 6.23 (d, J=15.7 Hz, 1H), 6.21 (d,J=15.8 Hz, 1H), 6.20 (s, 1H), 5.79 (dd, J=11.2, 2.3 Hz, 1H), 5.59 (dd,J=15.7, 7.5 Hz, 1H), 5.56 (d, J=9.9 Hz, 1H), 5.46 (ddd, J=13.1, 13.1,2.7 Hz, 1H), 5.38 (s, 1H), 5.22 (s, 1H), 4.78 (d, J=9.4 Hz, 1H), 4.77(s, 1H), 4.61 (dd, J=11.2, 4.4 Hz, 1H), 4.35 (app t, J=6.8 Hz, 1H), 4.02(m, 2H), 3.92 (m, 2H), 3.77 (m, 2H), 3.64 (app q, J=6.3 Hz, 1H), 3.42(m, 1H), 3.40 (d, J=10.1 Hz, 1H), 3.11 (d, J=13.8 Hz, 1H), 3.09 (s, 3H),3.07 (s, 3H), 2.97 (d, J=11.0 Hz, 1H), 2.84 (d, J=15.4 Hz, 1H), 2.69 (d,J=15.4 Hz, 1H), 2.63 (m, 1H), 2.41 (m, 5H), 2.29 (m, 2H), 2.03 (m, 4H),1.94 (s, 3H), 1.66 (d, J=0.9 Hz, 3H), 1.51 (m, 4H), 1.29 (m, 7H), 1.04(d, J=6.9 Hz, 3H), 0.74 (d, J=6.5 Hz, 3H); ¹³CNMR (125 MHz, C₆D₆) δ165.8, 161.7, 145.7, 143.8, 143.1, 139.1, 137.8, 137.2, 136.3, 134.4,133.8, 131.9, 127.9, 121.4, 120.2, 118.7, 110.4, 97.2, 89.7, 81.3, 81.0,80.1, 78.8, 73.8, 73.3, 71.4, 70.7, 69.9, 69.1, 67.5, 64.7, 56.6, 55.7,42.3, 41.5, 40.2, 40.1, 39.6, 37.9, 35.5, 34.9, 33.9, 33.1, 32.4, 32.0,31.2, 30.5, 30.1, 26.6, 23.4, 14.7, 13.7, 6.6; high resolution massspectrum (ES⁺) m/z 965.4766 [(M+Na)⁺; calcd for C₅₃H₇₀N₂O₁₃: 965.4776].

C(45-46)-Alkyl-Phorboxazole (−)-3.13:

Fully protected C(45-46)-alkyl-phorboxazole (+)-3.37 (13.1 mg, 0.010mmol) was introduced into a flame dried round bottom flask, azeotropedfrom benzene (3 mL, 3×) and dried under vacuum. After one hour, under anargon atmosphere, (+)-3.37 was dissolved in freshly distilled THF (2.7mL) and cooled to 0° C. Tetrabutylammonium fluoride (1.0 M/THF) (0.030mL, 0.030 mmol) was then added dropwise and after one hour, the reactionwas quenched via dropwise addition of saturated aqueous sodium chloride(2 mL) and the layers of the biphasic mixture were separated. Theaqueous layer was extracted with ethyl acetate (3 mL, 4×) and thecombined organic extracts were dried over MgSO₄, filtered andconcentrated under reduced pressure. At room temperature under an argonatmosphere, the resultant amorphous solid was dissolved in freshlydistilled THF (7.4 mL) followed by dropwise addition of 6% hydrogenchloride solution (2.9 mL). After thirty seven hours, the reactionmixture was cooled to 0° C., stirred for five minutes and poured intosaturated aqueous sodium bicarbonate (5 mL). The layers were separatedand the aqueous layer was extracted with dichloromethane (5 mL, 4×)followed by extraction with ethyl acetate (5 mL, 2×). The combinedorganic extracts were dried over MgSO₄, filtered and concentrated underreduced pressure. Purification via silica gel chromatography (100%EtOAc→10% CH₃OH/EtOAc) afforded C(45-46)-alkyl-phorboxazole

(−)-3.13 (8.1 mg, 86%) as an off white amorphous solid. [α]_(D) ²⁰−51.0(c 0.19, CH₂Cl₂); IR (neat) 3401 (b), 2921 (b), 1715 (s), 1451 (b), 1374(b), 1186 (s), 1157 (s), 1090 (s); ¹HNMR (500 MHz, C₆D₆) δ 7.02 (s, 1H),6.91 (s, 1H), 6.87 (m, 1H), 6.23 (d, J=15.8 Hz, 1H), 6.22 (s, 1H), 6.21(d, J=15.6 Hz, 1H), 5.79 (dd, J=11.4, 2.7 Hz, 1H), 5.58 (d, J=10.1 Hz,1H), 5.53 (dd, J=7.8, 4.1 Hz, 1H), 5.44 (ddd, J=10.8, 10.7, 2.6 Hz, 1H),5.25 (s, 1H), 4.81 (dd, J=11.2, 2.1 Hz, 1H), 4.78 (s, 1H), 4.61 (dd,J=11.2, 4.4 Hz, 1H), 4.38 (dd, J=15.7, 7.2 Hz, 1H), 4.35 (br s, 1H),4.08 (m, 2H), 3.97 (m, 2H), 3.79 (m, 2H), 3.52 (dd, J=12.5, 6.1 Hz, 1H),3.41 (m, 2H), 3.18 (s, 3H), 3.14 (m, 1H), 3.10 (dd, J=5.9, 2.2 Hz, 1H),3.07 (s, 3H), 3.01 (d, J=10.6 Hz, 1H), 2.86 (d, J=15.3 Hz, 1H), 2.74 (d,J=15.3 Hz, 1H), 2.65 (br s, 1H), 2.42 (m, 4H), 2.30 (dd, J=13.0, 5.4 Hz,1H), 2.02 (m, 5H), 1.93 (s, 3H), 1.80 (m, 1H), 1.68 (d, J=0.8 Hz, 3H),1.56 (m, 5H), 1.42 (m, 2H), 1.29 (m, 4H), 1.04 (d, J=6.8 Hz, 3H), 0.90(app t, J=5.8 Hz, 3H), 0.74 (d, J=6.4 Hz, 3H); ¹³CNMR (125 MHz, C₆D₆) δ165.9, 161.8, 161.3, 145.9, 143.9, 143.3, 139.2, 138.6, 137.7, 137.1,136.5, 134.5, 134.0, 131.4, 131.3, 128.0, 127.9, 121.5, 120.4, 118.9,110.7, 97.4, 89.9, 83.0, 80.3, 79.0, 73.9, 73.5, 71.6, 70.1, 69.3, 67.7,64.8, 56.6, 55.8, 42.5, 41.6, 40.4, 40.2, 39.8, 39.1, 38.1, 35.6, 35.1,34.1, 33.3, 32.6, 31.3, 19.6, 14.9, 14.0, 13.9, 6.8; high-resolutionmass spectrum (ES⁺) m/z 969.5174 [(M+Na)⁺; calcd for C₅₃H₇₄N₂O₁₃Na:969.5189].

C(45-46)-Alkenyl-Phorboxazole (+)-3.12:

Fully protected C(45-46)-alkenyl-phorboxazole (+)-3.36 (3.8 mg, 0.003mmol) was introduced into a flame dried round bottom flask, azeotropedfrom benzene (3 mL, 3×) and dried under vacuum. After one hour, under anargon atmosphere, (+)-3.36 was dissolved in freshly distilled THF (1mL), cooled to 0° C. and tetrabutylammonium fluoride (1.0 M/THF) (0.009mL, 0.009 mmol) was added dropwise. After one hour, the reaction wasquenched via dropwise addition of saturated aqueous sodium chloride (2mL) and the layers of the biphasic mixture were separated. The aqueouslayer was extracted with ethyl acetate (3 mL, 4×) and the combinedorganic extracts were dried over MgSO₄, filtered and concentrated underreduced pressure. At room temperature under an argon atmosphere, theresultant amorphous solid was dissolved in freshly distilled THF (5 mL)followed by dropwise addition of 6% hydrogen chloride solution (2.0 mL).After thirty seven hours, the reaction mixture was cooled to 0° C.,stirred for five minutes and poured into saturated aqueous sodiumbicarbonate (5 mL). The layers were separated and the aqueous layer wasextracted with dichloromethane (5 mL, 4×) followed by extraction withethyl acetate (5 mL, 2×). The combined organic extracts were dried overMgSO₄, filtered and concentrated under reduced pressure. Purificationvia silica gel chromatography, (100% EtOAc→10% CH₃OH/EtOAc) affordedC(45-46)-alkenyl-phorboxazole (+)-3.12 (1.9 mg, 67%) as an off whiteamorphous solid. [α]_(D) ²⁰+49.7 (c 0.51, CH₂Cl₂); IR (neat) 3404 (b),2927 (b), 1716 (s), 1661 (b), 1441 (b), 1372 (b), 1188 (s), 1161 (s),1092 (s); ¹HNMR (500 MHz, C₆D₆) δ 7.02 (s, 1H), 6.89 (s, 1H), 6.85 (m,1H), 6.21 (d, J=12.7 Hz, 1H), 6.20 (s, 1H), 6.18 (d, J=15.8 Hz, 1H),5.93 (m, 1H), 5.79 (dd, J=11.2, 2.4 Hz, 1H), 5.55 (d, J=8.6 Hz, 1H),5.53 (dd, J=15.7, 7.6 Hz, 1H), 5.45 (app t, J=10.4 Hz, 1H), 5.23 (s,1H), 5.07 (s, 1H), 5.06 (d, J=10.1 Hz, 1H), 4.79 (d, J=8.8 Hz, 1H), 4.78(s, 1H), 4.61 (dd, J=11.1, 4.4 Hz, 1H), 4.37 (m, 2H), 4.06 (m, 2H), 3.93(m, 2H), 3.78 (m, 2H), 3.56 (app q, J=6.4 Hz, 1H), 3.41 (m, 1H), 3.39(d, J=9.9 Hz, 1H), 3.14 (s, 3H), 3.13 (m, 1H), 3.07 (s, 3H), 2.99 (d,J=11.5 Hz, 1H), 2.83 (d, J=15.3 Hz, 1H), 2.69 (d, J=15.4 Hz, 1H), 2.65(app t, J=6.5 Hz, 1H), 2.40 (m, 4H), 2.27 (m, 2H), 2.04 (m, 2H), 1.98(d, J=12.3 Hz, 2H), 1.93 (s, 3H), 1.67 (d, J=0.8 Hz, 3H), 1.49 (m, 5H),1.28 (m, 6H), 1.04 (d, J=6.9 Hz, 3H), 0.73 (d, J=6.4 Hz, 3H); ¹³CNMR(125 MHz, C₆D₆) δ 165.8, 161.7, 161.2, 145.7, 143.7, 143.1, 139.0,138.4, 137.4, 137.2, 136.3, 135.5, 134.3, 133.8, 131.4, 130.4, 130.3,121.3, 120.2, 118.7, 117.2, 110.5, 97.3, 89.7, 82.6, 80.1, 78.8, 73.7,73.3, 71.4, 69.9, 69.1, 67.5, 64.7, 56.4, 55.7, 42.3, 41.4, 41.3, 40.2,40.0, 39.6, 37.9, 35.5, 34.9, 33.9, 33.1, 32.4, 31.2, 14.7, 13.8, 13.7,6.6; high resolution mass spectrum (ES⁺) m/z 967.4971 [(M+Na)⁺; calcdfor C₅₃H₇₂N₂O₁₃Na: 967.4931].

C(45-46)-E-Chloroalkenyl-Phorboxazole (+)-3.14:

Fully protected C(45-46)-E-chloroalkenyl-phorboxazole (+)-3.38 (8.2 mg,0.006 mmol) was introduced into a flame dried round bottom flask,azeotroped from benzene (3 mL, 3×) and dried under vacuum. After onehour, under an inert argon atmosphere, (+)-3.38 was dissolved in freshlydistilled THF (5.3 mL), cooled to 0° C. and tetrabutylammonium fluoride(1.0 M/THF) (0.018 mL, 0.018 mmol) was added dropwise. After one hour,the reaction was quenched via dropwise addition of saturated aqueoussodium chloride (5 mL) and allowed to stir for one minute. The layers ofthe biphasic mixture were separated and the aqueous layer extracted withethyl acetate (5 mL, 4×). The combined organic extracts were dried overMgSO₄, filtered and concentrated under reduced pressure. The resultantoff white amorphous solid, under an argon atmosphere was dissolved infreshly distilled THF (7.4 mL) followed by dropwise addition of 6%hydrogen chloride solution (2.9 mL). After stirring for thirty-six hoursat room temperature, the reaction was cooled to 0° C. and poured intosaturated aqueous sodium bicarbonate (5 mL). The resultant layers wereseparated and the aqueous layer extracted with dichloromethane (5 mL,4×) followed by ethyl acetate (5 mL, 2×). The combined organic extractswere dried over MgSO₄, filtered and concentrated under reduced pressure.Purification via silica gel chromatography, (100% EtOAc→10% CH₃OH/EtOAc)afforded C(45-46)-E-chloroalkenyl-phorboxazole (+)-3.14 (3.8 mg, 61%) asa white amorphous solid. [α]_(D) ²⁰+47.8 (c 0.39, CH₂Cl₂); IR (neat)3411 (b), 2926 (s), 1720 (s), 1647 (b), 1443 (b), 1375 (b), 1186 (s),1156 (s), 1088 (s), 991 (b); ¹HNMR (500 MHz, C₆D₆) δ 7.04 (s, 1H), 6.91(s, 1H), 6.87 (m, 1H), 6.22 (d, J=15.7 Hz, 1H), 6.21 (s, 1H), 6.10 (d,J=15.7 Hz, 1H), 5.98 (m, 1H), 5.80 (dd, J=11.0, 2.9 Hz, 1H), 5.74 (d,J=13.3 Hz, 1H), 5.55 (d, J=8.8 Hz, 1H), 5.45 (ddd, J=12.7, 12.6, 1.2 Hz,1H), 5.37 (dd, J=15.7, 7.8 Hz, 1H), 5.24 (s, 1H), 4.81 (d, J=11.1 Hz,1H), 4.78 (s, 1H), 4.61 (dd, J=11.1, 4.3 Hz, 1H), 4.37 (m, 2H), 4.08 (m,2H), 3.96 (m, 2H), 3.80 (m, 2H), 3.41 (m, 1H), 3.39 (d, J=9.9 Hz, 1H),3.36 (app q, J=7.3 Hz, 1H), 3.08 (s, 3H), 3.04 (s, 3H), 3.00 (dd,J=11.1, 0.9 Hz, 1H), 2.86 (d, J=15.3 Hz, 1H), 2.74 (d, J=15.3 Hz, 1H),2.65 (app t, J=5.2 Hz, 1H), 2.42 (m, 4H), 2.30 (dd, J=12.1, 4.3 Hz, 1H),2.11 (m, 1H), 2.01 (m, 6H), 1.92 (d, J=0.5 Hz, 3H), 1.63 (d, J=0.9 Hz,3H), 1.54 (m, 4H), 1.29 (m, 6H), 1.05 (d, J=6.8 Hz, 3H), 0.73 (d, J=6.4Hz, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 165.1, 161.0, 160.5, 145.1, 143.1,142.4, 138.4, 137.7, 136.9, 136.6, 135.6, 133.6, 133.2, 131.2, 129.9,127.2, 120.7, 119.6, 119.2, 118.1, 109.8, 96.6, 89.1, 81.1, 79.4, 78.1,73.1, 72.6, 70.7, 69.3, 68.5, 66.9, 64.0, 55.7, 55.0, 41.6, 40.7, 39.5,39.4, 39.0, 37.4, 37.3, 34.8, 34.3, 33.6, 33.2, 32.4, 31.7, 30.5, 14.1,14.0, 13.1, 6.0; high resolution mass spectrum (ES⁺) m/z 1002.5813[(M+Na)⁺ calcd for C₅₃H₇₁ClN₂O₁₃Na: 1002.5801].

E-C(2-3)-C(45-46)-Alkynyl-Phorboxazole (+)-3.15:

Fully protected E-C(2-3)-C(45-46)-alkynyl-phorboxazole (+)-3.39 (6.8 mg,0.005 mmol) was introduced into a flame dried round bottom flask,azeotroped from benzene (3 mL, 3×) and dried under vacuum. After onehour, under an inert argon atmosphere, (+)-3.39 was dissolved in freshlydistilled THF (1.3 mL) followed by dropwise introduction oftetrabutylammonium fluoride (1.0 M/THF) (0.015 mL, 0.015 mmol). Afterone hour, the reaction was quenched via dropwise addition of saturatedaqueous sodium chloride (2 mL). After stirring for one minute at 0° C.,the layers of the biphasic mixture were separated and the aqueous phasewas extracted with ethyl acetate (5 mL, 4×). The combined organicextracts were dried over MgSO₄, filtered and concentrated under reducedpressure. The resultant amorphous solid, under an inert argon atmospherewas dissolved in freshly distilled THF (4.7 mL) followed by dropwiseintroduction of 6% hydrogen chloride solution (1.9 mL) and allowed tostir at room temperature. After thirty six hours, the reaction wascooled to 0° C. and poured into saturated aqueous sodium bicarbonate (5mL). The biphasic mixture was separated and the aqueous layer wasextracted with dichloromethane (5 mL, 4×) followed by extraction withethyl acetate (5 mL, 2×). The combined organic extracts were dried overMgSO₄, filtered and concentrated under reduced pressure. Purificationvia silica gel chromatography, 100% EtOAc→10% CH₃OH/EtOAc) affordedE-C(2-3)-C(45-46)-alkynyl-phorboxazole (+)-3.15 (3.3 mg, 69%) as an offwhite amorphous solid. [α]_(D) ²⁰+51.6 (c 0.31, CH₂Cl₂); IR (neat) 3431(b), 2924 (s), 1695 (s), 1195 (b), 993 (s); ¹HNMR (500 MHz, C₆D₆) δ 7.00(s, 1H), 6.93 (s, 1H), 6.86 (m, 1H), 6.23 (d, J=15.7 Hz, 1H), 6.15 (d,J=14.5 Hz, 1H), 6.13 (s, 1H), 6.05 (d, J=15.1 Hz, 1H), 5.59 (dd, J=15.6,7.5 Hz, 1H), 5.56 (d, J=8.9 Hz, 1H), 5.47 (s, 1H), 5.07 (dd, J=10.8, 3.8Hz, 1H), 4.82 (dd, J=11.7, 2.1 Hz, 1H), 4.7 (s, 1H), 4.62 (s, 1H), 4.35(app t, J=7.3 Hz, 1H), 4.31 (br s, 1H), 3.97 (dd, J=10.4, 7.6 Hz, 1H),3.83 (m, 3H), 3.63 (app q, J=6.7 Hz, 1H), 3.45 (br s, 1H), 3.37 (m, 1H),3.34 (d, J=10.0 Hz, 1H), 3.09 (s, 3H), 3.08 (s, 3H), 2.84 (d, J=15.3 Hz,1H), 2.70 (d, J=16.0 Hz, 1H), 2.51 (br s, 1H), 2.45 (dd, J=5.7, 2.6 Hz,1H), 2.35 (dd, J=6.6, 2.6 Hz, 1H), 2.27 (m, 4H), 2.11 (m, 3H), 1.96 (m,4H), 1.89 (s, 3H), 1.79 (m, 2H), 1.70 (m, 2H), 1.66 (d, J=3.4 Hz, 3H),1.48 (d, J=12.6 Hz, 1H), 1.32 (m, 4H), 1.22 (m, 3H), 0.85 (d, J=6.6 Hz,3H), 0.82 (d, J=6.5 Hz, 3H); ¹³CNMR (125 MHz, C₆D₆) δ 167.5, 162.5,161.2, 147.6, 143.8, 142.8, 139.3, 138.6, 138.0, 137.4, 136.4, 134.5,132.2, 128.0, 127.9, 124.2, 119.1, 118.8, 111.4, 100.9, 99.2, 97.4,89.7, 81.5, 81.2, 79.2, 77.3, 74.0, 73.9, 73.4, 71.6, 71.0, 70.9, 66.1,64.9, 56.8, 55.9, 41.6, 41.3, 40.3, 39.5, 38.6, 38.5, 38.3, 38.0, 35.5,34.0, 30.7, 26.7, 26.7, 14.8, 13.9, 6.1; high resolution mass spectrum(ES⁺) m/z 965.4831 [(M+Na)⁺; calcd for C₅₃H₇₀N₂O₁₃Na: 965.4843].

C(45-46)-Alkenyl-C(22-26)-Central Tetrahydropyran Phorboxazole (−)-3.41:

Fully protected C(45-46)-alkenyl-C(22-26)-central tetrahydropyranphorboxazole (−)-3.40 (12.9 mg, 0.011 mmol) was introduced into a flamedried round bottom flask, azeotroped from benzene (5 mL, 3×) and driedunder vacuum. After one hour, under an argon atmosphere, (−)-3.40 wasdissolved in freshly distilled THF (2.7 mL), followed by cooling to 0°C. and dropwise addition of tetrabutylammonium fluoride (1.0 M/THF)(0.022 mL, 0.022 mmol). After one hour, the reaction was warmed to roomtemperature and after 2.5 total hours of reacting, the reaction wasquenched via dropwise addition of saturated aqueous sodium chloride (3mL). The layers of the biphasic mixture were separated and the aqueouslayer was extracted with ethyl acetate (5 mL, 4×). The combined organicextracts were dried over MgSO₄, filtered and concentrated under reducedpressure. The resultant off white amorphous solid, under an argonatmosphere was dissolved in freshly distilled THF (7.1 mL) followed bydropwise introduction of 6% hydrogen chloride solution (2.8 mL). Afterstirring at room temperature for thirty six hours, the reaction wascooled to 0° C. and poured into saturated aqueous sodium bicarbonate (5mL). The layers of the resultant biphasic mixture were separated and theaqueous layer was extracted with dichloromethane (5 mL, 4×) followed byextraction with ethyl acetate (5 mL, 2×). The combined organic extractswere dried over MgSO₄, filtered and concentrated under reduced pressure.Purification via silica gel chromatography, (100% EtOAc→10% CH₃OH/EtOAc)afforded C(45-46)-alkenyl-C(22-26)-central tetrahydropyran phorboxazole(−)-3.41 (7.1 mg, 66%) as an off white amorphous solid. [α]_(D) ²⁰−69.0(c 0.16, CH₂Cl₂); IR (neat) 2921 (b), 1515 (s), 1454 (b), 1420 (s), 1376(b), 1260 (s), 1238 (s), 1152 (s), 1087 (b), 1027 (s), 966 (s); ¹HNMR(500 MHz, C₆D₆) δ 6.99 (s, 1H), 6.97 (d, J=1.8 Hz, 1H), 6.92 (dd, J=8.0,1.7 Hz, 1H), 6.67 (d, J=8.1 Hz, 1H), 6.19 (s, 1H), 6.18 (d, J=15.7 Hz,1H), 5.92 (m, 1H), 5.54 (d, J=8.6 Hz, 1H), 5.52 (dd, J=15.6, 7.6 Hz,1H), 5.40 (s, 1H), 5.08 (d, J=15.9 Hz, 2H), 5.05 (d, J=10.1 Hz, 1H),4.52 (d, J=11.4 Hz, 1H), 4.36 (app t, J=7.3 Hz, 1H), 4.21 (d, J=11.4 Hz,1H), 3.96 (dddd, J=11.8, 6.9, 5.0, 4.8 Hz, 1H), 3.77 (m, 1H), 3.64 (m,2H), 3.56 (app q, J=6.5 Hz, 1H), 3.52 (s, 3H), 3.44 (s, 3H), 3.35 (d,J=10.3 Hz, 1H), 3.14 (s, 3H), 3.07 (s, 3H), 3.06 (m, 2H), 2.84 (d,J=15.4 Hz, 1H), 2.70 (d, J=15.5 Hz, 1H), 2.44 (m, 2H), 2.29 (m, 2H),1.97 (d, J=14.5 Hz, 1H), 1.91 (m, 3H), 1.88 (d, J=0.9 Hz, 3H), 1.66 (d,J=1.1 Hz, 3H), 1.31 (m, 4H), 1.07 (d, J=6.9 Hz, 3H), 0.90 (d, J=6.4 Hz,3H); ¹³CNMR (125 MHz, C₆D₆) δ 161.0, 150.7, 150.2, 139.4, 138.3, 137.3,137.3, 136.2, 135.5, 132.2, 131.5, 130.1, 120.5, 118.7, 117.2, 112.6,112.5, 97.2, 89.5, 83.4, 82.6, 77.7, 73.7, 73.3, 71.4, 70.2, 61.2, 56.4,56.1, 56.0, 55.7, 41.5, 41.2, 40.1, 36.3, 35.4, 33.9, 33.9, 14.6, 14.3,13.7, 6.8; high resolution mass spectrum (ES⁺) m/z 778.4134 [(M+Na)⁺;calcd for C₄₂H₆INO₁₁Na: 778.4141].

Diol (−)-3.49:

To a solution of β-Hydroxyimide (−)-3.50 (Smith, et al. J. Am. Chem.Soc. 2001, 123, 10942) (1.0 g, 1.56 mmol) in diethyl ether (6.25 mL) at0° C. under argon was added H₂O (0.031 mL, 1.72 mmol) and LiBH₄ (0.037g, 1.72 mmol) in one portion. After stirring at 0° C. for 10 minutes,the reaction was warmed to room temperature, stirred for 10 minutes,cooled back to 0° C. and quenched with pH 7 phosphate buffer (7 mL). Thelayers of the biphasic mixture were separated and the aqueous layer wasextracted with diethyl ether (20 mL, 3×). The combined organic extractswere washed with saturated aqueous sodium chloride (20 mL, 1×), driedover MgSO₄, filtered and concentrated under reduced pressure.Purification via silica gel chromatography (50% EtOAc/hexanes) afforded(−)-3.49 (0.604 g, 83% yield) as a colorless oil: [α]_(D) ²⁰−18.3 (c1.0, CHCl₃); IR (neat) 3397 (b), 3070 (w), 2939 (s), 2857 (s), 1654 (w),1472 (w), 1428 (s), 1389 (w), 1110 (s), 890 (m), 823 (m), 740 (m), 701(s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.67 (m, 4H), 7.40 (m, 6H), 4.78 (s,1H), 4.72 (s, 1H), 4.25 (m, 1H), 3.92 (m, 1H), 3.89 (s, 1H), 3.76 (m,4H), 3.67 (ddd, J=10.8, 6.7, 5.6 Hz, 1H), 2.87 (dd, J=6.7, 4.5 Hz, 1H),2.45 (dd, J=13.4, 5.6 Hz, 1H), 2.21 (dd, J=13.1, 3.0 Hz, 1H), 2.01 (m,2H), 1.94 (dddd, J=14.1, 8.6, 5.6, 5.6 Hz, 1H), 1.75 (ddd, J=14.5, 10.1,10.1 Hz, 1H), 1.65 (m, 3H), 1.43 (ddd, J=14.5, 2.2, 2.2 Hz, 1H), 1.05(s, 9H); ¹³CNMR (125 MHz, CDCl₃) δ 141.0, 135.4, 135.3, 133.6, 133.4,129.5, 129.4, 127.58, 127.52, 110.5, 71.7, 71.5, 70.1, 61.0, 60.3, 41.4,40.5, 38.55, 38.53, 34.3, 26.7, 18.9; high resolution mass spectrum(ES⁺) m/z 491.2686 [(M+Na)⁺; calcd for C₂₈H₄₀O₄SiNa: 491.2593].

C(11-15) Acetal (−)-3.51:

Under an argon atmosphere at −78° C., 1,1,1,3,3,3-hexamethydisilazane(HMDS) (0.93 mL, 4.41 mmol) was added dropwise via syringe to a stirredsolution of diol (−)-3.49 (1.97 g, 4.21 mmol) in CH₂Cl₂ (10 mL).Following the addition, the reaction was warmed to room temperature.After twenty hours, the reaction was concentrated under reduced pressurefollowed by drying under vacuum (to remove excess1,1,1,3,3,3-hexamethyldisilazane) to provide the correspondingbis-silylated diol, which was used without further purification. Underan argon atmosphere at 0° C., trimethylsilyl trifluoromethanesulfonate(TMSOTf) (0.148 mL, 0.82 mmol) was added dropwise to a solution ofoxazole 3.48 (Smith, et al. Org. Lett. 1999, 1, 909) (2.00 g, 8.11 mmol)and the bis-silylated diol in CH₂Cl₂ (21 mL). After stirring for fifteenhours, the reaction was cooled to −78° C., quenched with triethylamine(2.35 mL, 16.8 mmol), and warmed to room temperature over one hour. Thereaction was diluted with saturated aqueous sodium bicarbonate (20 mL)and extracted with CH₂Cl₂ (10 mL, 3×). The combined organic extractswere dried over MgSO₄, filtered and concentrated under reduced pressure.Purification via silica gel chromatography (10% EtOAc/hexanes→20%EtOAc/hexanes) afforded C(11-15) acetal (−)-3.51 (2.52 g, 86% yield) asa light yellow oil: [α]_(D) ²⁰−16.1 (c 0.5, CHCl₃); IR (neat) 3150 (w),3070 (m), 2930 (s), 2856 (s), 1889 (w), 1821 (w), 1727 (w), 1653 (m),1612 (s), 1586 (m), 1513 (s), 1464 (m), 1428 (s), 1375 (m), 1302 (m),1249 (s), 1175 (m), 1111 (s), 1036 (s), 822 (s), 741 (m), 704 (s) 614(m) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.66 (m, 5H), 7.39 (m, 6H), 7.26 (m,2H), 6.87 (m, 2H), 5.44 (s, 1H), 4.75 (s, 2H), 4.55 (s, 2H), 4.52 (s,2H), 4.14 (dd, J=11.5, 4.8 Hz, 1H), 4.03 (m, 1H), 3.87 (m, 2H), 3.80 (s,3H), 3.72 (m, 3H), 2.34 (ddd, J=13.0, 3.4, 3.4 Hz, 2H), 2.10 (ddd,J=14.1, 8.2, 5.6 Hz, 1H), 2.00 (m, 2H), 1.85 (m, 1H), 1.73 (m, 1H), 1.67(m, 2H), 1.51 (m, 1H), 1.05 (s, 9H); ¹³CNMR (125 MHz, CDCl₃) δ 161.1,159.4, 141.8, 139.1, 136.9, 135.5, 133.82, 133.79, 129.7, 129.6, 129.2,127.63, 127.58, 113.84, 113.81, 110.4, 96.1, 74.0, 72.5, 68.9, 67.8,66.8, 63.5, 60.6, 55.2, 39.7, 39.6, 39.0, 36.4, 30.7, 29.6, 26.8, 19.1;high resolution mass spectrum (ES⁺) m/z 698.3538 [(M+H)⁺; calcd forC₄₁H₅INO₇SiH: 698.3513].

Alcohol Tricycle (−)-3.S₄:

2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) (1.24 g, 5.47 mmol) wasadded as one portion to a solution of C(11-15) acetal (−)-3.51 (1.80 g,2.60 mmol) in CH₂Cl₂ (260 mL) and H₂O (17.4 mL) at room temperatureunder an argon atmosphere. After stirring for twelve hours, the reactionwas quenched via dropwise addition of saturated aqueous sodiumbicarbonate (30 mL). The layers of the biphasic mixture were separatedand the aqueous layer was extracted with CH₂Cl₂ (20 mL, 4×). Thecombined organic extracts were dried over MgSO₄, filtered andconcentrated under reduced pressure. Purification via silica gelchromatography (50% EtOAc/hexanes) afforded alcohol tricycle (−)-3.S₄(1.26 g, 84% yield) as a light yellow oil: [α]_(D) ²⁰−18.9 (c 0.5,CHCl₃); IR (neat) 3376 (b), 3158 (w), 3071 (m), 2931 (s), 2857 (s), 1901(w), 1828 (w), 1652 (m), 1578 (m), 1471 (m), 1428 (s), 1375 (m), 1237(m), 1185 (m), 1112 (s), 1038 (s), 1010 (m), 937 (w), 893 (w), 823 (s),757 (s), 704 (s), 614 (m) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.66 (m, 4H),7.61 (s, 1H), 7.40 (m, 6H), 5.43 (s, 1H), 4.75 (s, 2H), 4.71 (s, 1H),4.69 (s, 1H), 4.14 (dd, J=12.3, 4.8 Hz, 1H), 4.01 (m, 1H), 3.87 (m, 2H),3.75 (m, 2H), 3.68 (m, 1H), 2.44 (m, 1H), 2.34 (ddd, J=13.4, 3.7, 3.7Hz, 2H), 2.11 (ddd, J=14.1, 8.9, 5.6 Hz, 1H), 1.99 (m, 2H), 1.86 (m,1H), 1.76 (m, 1H), 1.67 (m, 1H), 1.51 (m, 2H), 1.05 (s, 9H); ¹³CNMR (125MHz, CDCl₃) δ 163.1, 141.8, 139.0, 136.5, 135.5, 133.8, 129.7, 129.6,127.63, 127.62, 127.60, 127.58, 110.4, 95.9, 74.0, 68.9, 67.8, 66.8,60.6, 57.6, 39.7, 39.6, 39.0, 36.4, 30.7, 26.8, 19.1; high resolutionmass spectrum (ES⁺) m/z 600.2766 [(M+Na)⁺; calcd for C₃₃H₄₃NO₆SiNa:600.2757].

Mesylate Tricycle (−)-3.52:

N,N-Diisopropylethylamine (0.65 mL, 3.75 mmol) followed by dropwiseaddition of methanesulfonyl chloride (0.17 mL, 2.25 mmol) were added toa solution of alcohol tricycle (−)-3.S₄ (1.08 g, 1.87 mmol) in CH₂Cl₂(117 mL) at 0° C. under an argon atmosphere. After one hour, thereaction mixture was filtered through a plug of silica gel (40%EtOAc/hexanes) to afford mesylate tricycle (−)-3.52 (1.20 g, 98% yield)as a colorless oil: [α]_(D) ²⁰−15.2 (c 1.0, CHCl₃); IR (neat) 3071 (w),2933 (s), 2857 (s), 1653 (w), 1587 (w), 1472 (w), 1428 (m), 1353 (s),1238 (w), 1177 (s), 1112 (s), 1034 (m), 958 (m), 822 (w), 743 (w), 704(s), 613 (m) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.70 (s, 1H), 7.66 (m, 4H),7.39 (m, 6H), 5.43 (s, 1H), 5.25 (s, 2H), 4.75 (br s, 2H), 4.14 (dd,J=12.3, 4.8 Hz, 1H), 4.01 (m, 1H), 3.87 (m, 2H), 3.72 (m, 3H), 3.06 (s,3H), 2.35 (dd, J=13.0, 3.7 Hz, 2H), 2.10 (ddd, J=14.1, 8.9, 5.6 Hz, 1H),2.00 (m, 2H), 1.85 (dddd, J=14.1, 8.6, 5.6, 5.6 Hz, 1H), 1.71 (m, 1H),1.67 (m, 1H), 1.52 (m, 2H), 1.05 (s, 9H); ¹³CNMR (125 MHz, CDCl₃) δ156.7, 141.7, 140.0, 138.0, 135.5, 133.8, 129.7, 129.6, 127.65, 127.64,127.61, 127.60, 110.5, 95.7, 74.1, 68.9, 67.8, 66.8, 61.7, 60.6, 39.7,39.6, 39.0, 38.3, 36.4, 30.7, 26.8, 19.1; high resolution mass spectrum(ES⁺) m/z 678.2509 [(M+Na)⁺; calcd for C₃₄H₄₅NO₈SSiNa: 678.2533].

C(19-20) E-Olefin (+)-3.53:

Tri-n-butylphosphine (0.56 mL, 2.24 mmol) was added dropwise to astirred solution of mesylate tricycle (−)-3.52 (0.37 g, 0.56 mmol) inanhydrous N,N-dimethylformamide (DMF) (119 mL) at room temperature underan argon atmosphere. After stirring for twenty-four hours, a solution ofaldehyde (+)-2.12 (0.27 g, 0.56 mmol) in DMF (63 mL) was introduceddropwise via cannula. Following five minutes of stirring,1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (0.17 mL, 1.12 mmol) was addeddropwise via syringe. After one hour, the reaction was diluted withdiethyl ether (50 mL), poured into H₂O (50 mL), and the organic layerwas washed with H₂O (20 mL, 5×). The combined organic extracts werewashed with saturated aqueous sodium chloride (20 mL, 1×), dried overMgSO₄, filtered, and concentrated under reduced pressure. Purificationvia silica gel chromatography (25% EtOAc/hexanes) afforded C(19-20)E-olefin (+)-3.53 (0.53 g, 91% yield, 19:1, E:Z) as a light yellow oil:[α]_(D) ²⁰+22.2 (c 1.0, CHCl₃); IR (neat) 3070 (m), 2928 (s), 2855 (s),1653 (m), 1592 (m), 1516 (s), 1463 (s), 1427 (s), 1388 (w), 1263 (m),1238 (m), 1139 (m), 1110 (s), 1031 (s), 972 (m), 893 (w), 857 (w), 822(w), 756 (s), 704 (s), 614 (m) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.66 (m,4H), 7.54 (s, 1H), 7.39 (m, 6H), 6.89 (s, 1H), 6.87 (d, J=8.3 Hz, 1H),6.83 (d, J=8.1 Hz, 1H), 6.68 (m, 1H), 6.34 (d, J=16.4 Hz, 1H), 6.23 (s,1H), 5.43 (s, 1H), 4.75 (br s, 2H), 4.57 (d, J=11.2 Hz, 1H), 4.28 (d,J=11.2 Hz, 1H), 4.14 (dd, J=11.5, 4.8 Hz, 1H), 3.99 (m, 1H), 3.87 (s,3H), 3.86 (s, 3H), 3.73 (m, 3H), 3.51 (d, J=10.4 Hz, 1H), 3.47 (m, 1H),3.14 (dd, J=10.1, 4.5 Hz, 1H), 2.56 (ddd, J=14.5, 6.3, 6.3 Hz, 1H), 2.35(m, 3H), 2.11 (m, 2H), 2.00 (m, 2H), 1.82 (s, 3H), 1.80 (m, 2H), 1.68(m, 1H), 1.51 (m, 2H), 1.26 (s, 3H), 1.05 (s, 9H), 0.97 (d, J=6.7 Hz,3H), 0.80 (d, J=6.3 Hz, 3H); ¹³CNMR (125 MHz, CDCl₃) δ 161.1, 149.0,148.6, 146.2, 141.8, 139.8, 135.9, 135.5, 135.3, 133.8, 131.0, 129.6,127.64, 127.63, 127.61, 127.60, 120.2, 118.4, 111.1, 110.9, 110.4, 96.2,87.5, 82.8, 81.0, 77.4, 77.2, 74.0, 69.9, 68.9, 67.8, 66.8, 60.7, 55.9,55.8, 39.7, 39.6, 39.1, 36.4, 36.1, 33.5, 33.3, 30.7, 29.6, 26.8, 19.1,13.5, 5.7; high resolution mass spectrum (ES⁺) m/z 1032.3949 [(M+H)⁺;calcd for C₅₄H₇₀INO₉SiH: 1032.3943].

Primary Alcohol (+)-3.S₅:

Tetrabutylammonium fluoride (TBAF) (1.0 M/THF, 0.22 mL, 0.22 mmol) wasadded dropwise via syringe to a solution of (+)-3.53 (0.21 g, 0.20 mmol)in freshly distilled tetrahydrofuran (THF) (2 mL) at room temperatureunder an argon atmosphere. After two hours, the reaction was quenchedvia dropwise addition of saturated aqueous sodium chloride (10 mL). Thelayers of the biphasic solution were separated and the aqueous layer wasextracted with EtOAc (7 mL, 4×). The combined organic extracts weredried over MgSO₄, filtered, and concentrated under reduced pressure.Purification via silica gel chromatography (80% EtOAc/hexanes) affordedprimary alcohol (+)-3.S₅ (0.14 g, 89% yield) as a light yellow oil:[α]_(D) ²⁰+37.6 (c 1.0, CHCl₃); IR (neat) 3407 (b), 3071 (w), 2940 (s),2855 (s), 1659 (m), 1594 (w), 1516 (s), 1463 (m), 1420 (w), 1375 (w),1263 (m), 1238 (m), 1139 (m), 1102 (s), 1030 (s), 973 (m), 808 (w), 754(s), 668 (w) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 7.60 (s, 1H), 6.86 (m, 3H),6.68 (m, 1H), 6.34 (d, J=16.0 Hz, 1H), 6.22 (d, J=1.1 Hz, 1H), 5.56 (s,1H), 4.79 (s, 1H), 4.74 (s, 1H), 4.56 (d, J=11.5 Hz, 1H), 4.27 (d,J=11.2 Hz, 1H), 4.24 (dd, J=11.1, 3.6 Hz, 1H), 4.10 (m, 1H), 4.01 (m,1H), 3.94 (m, 2H), 3.87 (s, 3H), 3.87 (s, 3H), 3.74 (m, 2H), 3.5 (d,J=10.4 Hz, 1H), 3.46 (ddd, J=7.1, 7.1, 1.9 Hz, 1H), 3.14 (dd, J=10.4,4.5 Hz, 1H), 2.75 (br s, 1H), 2.56 (m, 1H), 2.42 (dd, J=13.0, 4.8 Hz,1H), 2.36 (m, 1H), 2.29 (dd, J=13.0, 4.1 Hz, 1H), 2.20 (ddd, J=14.9,8.9, 6.3 Hz, 1H), 2.11 (m, 1H), 2.04 (m, 3H), 1.82 (m, 3H), 1.81 (d,J=1.1 Hz, 3H), 1.61 (m, 1H), 1.54 (m, 1H), 0.96 (d, J=7.1 Hz, 3H), 0.79(d, J=6.3 Hz, 3H); ¹³CNMR (125 MHz, CDCl₃) δ 161.2, 149.0, 148.6, 146.2,141.3, 139.7, 136.1, 135.4, 131.0, 120.2, 118.3, 111.1, 110.9, 110.7,92.3, 87.5, 82.8, 80.9, 77.3, 74.7, 70.9, 69.8, 69.4, 66.9, 60.5, 55.9,55.8, 40.1, 39.1, 38.2, 36.3, 36.1, 33.6, 33.3, 31.1, 19.1, 13.5, 5.6;high-resolution mass spectrum (ES⁺) m/z 816.2545 [(M+Na)⁺; calcd forC₃₉H₅₂INO₉Na: 816.2585].

Aldehyde (+)-3.54:

Solid sodium bicarbonate (0.02 g, 0.20 mmol) followed by the Dess-Martinperiodinane (0.17 g, 0.40 mmol) were added to a solution of primaryalcohol (+)-3.S₅ (0.158 g, 0.20 mmol) in CH₂Cl₂ (75 mL) at 0° C. underan argon atmosphere. After stirring for ten minutes, the reaction waswarmed to room temperature and after one hour and thirty minutes, thereaction was quenched via dropwise addition of saturated aqueous sodiumbicarbonate (15 mL). The layers of the biphasic mixture were separatedand the aqueous layer was extracted with CH₂Cl₂ (15 mL, 4×), dried overMgSO₄, filtered, and concentrated under reduced pressure. Purificationvia silica gel chromatography (70% EtOAc/hexanes) afforded aldehyde(+)-3.54 (0.135 g, 86% yield): [α]_(D) ²⁰+36.5 (c 1.0, CHCl₃); IR (neat)3151 (w), 3071 (w), 2934 (s), 2853 (s), 2726 (w), 1724 (s), 1659 (m),1593 (m), 1516 (s), 1462 (m), 1420 (m), 1375 (m), 1263 (s), 1238 (s),1156 (w), 1138 (s), 1101 (s), 1029 (s), 973 (m), 912 (m), 808 (w), 766(w), 731 (s) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 9.76 (dd, J=3.0, 1.5 Hz,1H), 7.60 (s, 1H), 6.85 (m, 3H), 6.67 (m, 1H), 6.33 (d, J=16.0 Hz, 1H),6.22 (d, J=1.1 Hz, 1H), 5.56 (s, 1H), 4.8 (s, 2H), 4.56 (d, J=11.2 Hz,1H), 4.40 (dddd, J=8.9, 7.1, 4.5, 4.5 Hz, 1H), 4.27 (d, J=11.2 Hz, 1H),4.23 (dd, J=11.1, 3.6 Hz, 1H), 3.96 (m, 3H), 3.87 (s, 3H), 3.86 (s, 3H),3.50 (d, J=10.4 Hz, 1H), 3.46 (ddd, J=7.1, 7.1, 1.9 Hz, 1H), 3.14 (dd,J=10.4, 4.8 Hz, 1H), 2.70 (m, 1H), 2.53 (m, 1H), 2.47 (dd, J=16.4, 4.8Hz, 1H), 2.37 (m, 3H), 2.15 (ddd, J=14.5, 9.3, 5.6 Hz, 1H), 2.10 (ddd,J=6.7, 4.8, 1.5 Hz, 1H), 2.03 (m, 2H), 1.80 (d, J=1.1 Hz, 3H), 1.77 (m,1H), 1.56 (m, 2H), 1.25 (app t, J=7.1 Hz, 1H), 0.96 (d, J=7.1 Hz, 3H),0.79 (d, J=6.3 Hz, 3H); ¹³CNMR (125 MHz, CDCl₃) δ 200.5, 161.2, 149.0,148.6, 146.2, 140.5, 139.8, 136.0, 135.3, 130.9, 120.2, 118.4, 111.4,111.1, 110.9, 96.3, 87.5, 82.8, 80.9, 77.3, 74.0, 69.9, 68.8, 67.2,66.9, 55.9, 55.8, 47.1, 39.4, 39.2, 38.8, 36.1, 33.5, 33.3, 30.8, 19.1,13.5, 5.7; high resolution mass spectrum (ES⁺) m/z 814.2392 [(M+Na)⁺;calcd for C₃₉H₅₀INO₉Na: 814.2428].

Secondary Alcohol-Aldehyde (+)-3.44:

2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) (0.079 g, 0.35 mmol) andpH 7 phosphate buffer (5.7 mL) were added to a solution of aldehyde(+)-3.54 (0.137 g, 0.17 mmol) in CH₂Cl₂ (24 mL) at room temperatureunder an argon atmosphere. After three hours and thirty minutes, thereaction mixture was poured into saturated aqueous sodium bicarbonate(20 mL). The layers of the biphasic mixture were separated and theaqueous layer was extracted with CH₂Cl₂ (15 mL, 4×). The combinedorganic extracts were dried over MgSO₄, filtered, and concentrated underreduced pressure. Purification via silica gel chromatography (80%EtOAc/hexanes) afforded secondary alcohol-aldehyde (+)-3.44 (0.108 g,98% yield) as a light yellow oil: [α]_(D) ²⁰+34.7 (c 1.0, CHCl₃); IR(neat) 3420 (b), 3151 (w), 3071 (w), 2924 (s), 2855 (s), 2726 (w), 1718(s), 1654 (s), 1618 (w), 1541 (m), 1457 (m), 1279 (w), 1100 (s), 1012(s), 892 (w), 755 (m), 671 (w) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 9.76 (dd,J=3.0, 1.5 Hz, 1H), 7.59 (s, 1H), 6.66 (m, 1H), 6.33 (d, J=16.0 Hz, 1H),6.23 (d, J=1.1 Hz, 1H), 5.55 (s, 1H), 4.80 (s, 2H), 4.40 (m, 1H), 4.23(dd, J=11.2, 4.8 Hz, 1H), 3.95 (m, 3H), 3.51 (m, 1H), 3.50 (d, J=10.2Hz, 1H), 3.43 (dd, J=10.4, 4.5 Hz, 1H), 2.70 (m, 1H), 2.54 (m, 1H), 2.50(dd, J=16.4, 4.8, Hz, 1H), 2.48 (ddd, J=16.4, 4.8, 1.5 Hz, 2H), 2.32 (m,1H), 2.12 (ddd, J=14.5, 9.3, 5.6 Hz, 1H), 2.03 (m, 2H), 1.9 (m, 1H),1.81 (d, J=1.1 Hz, 3H), 1.60 (m, 5H), 0.95 (d, J=7.1 Hz, 3H), 0.81 (d,J=6.7 Hz, 3H); ¹³CNMR (125 MHz, CDCl₃) δ 200.5, 161.2, 146.0, 140.5,139.8, 136.0, 135.3, 118.3, 111.4, 96.3, 87.3, 80.9, 77.6, 76.3, 74.0,68.7, 67.2, 66.9, 47.6, 39.4, 39.2, 38.8, 38.0, 35.9, 34.5, 30.8, 19.2,13.1, 5.4; high resolution mass spectrum (ES⁺) m/z 642.1911 [(M+H)⁺;calcd for C₂₉H₄₀INO₇H, 642.1928].

Phosphonate Ester (+)-3.S₆:

A solution of bis-(2,2,2-trifluoroethyl)phosphonate acid 3.45 (0.522 g,1.72 mmol) in CH₂Cl₂ (30 mL) was added via cannula to a solution ofsecondary alcohol-aldehyde (+)-3.44 (0.221 g, 0.34 mmol) in CH₂Cl₂ (40mL) at room temperature under an argon atmosphere. After stirring forten minutes, 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide-methiodide(EDCI.MeI) (0.511 g, 1.72 mmol) and 1-hydroxybenzotriazole (HOBT) (0.005g, 0.03 mmol) were added to the reaction mixture. After forty-fiveminutes, the reaction was filtered through a plug of silica gel (80%EtOAc/hexanes) to afford phosphonate ester (+)-3.S₆ (0.261 g, 82% yield)as a light yellow oil: [α]_(D) ²⁰+17.6 (c 1.0, CHCl₃); IR (neat) 3077(w), 2924 (s), 2855 (m), 2726 (w), 1728 (s), 1656 (w), 1624 (w), 1539(w), 1419 (m), 1397 (w), 1305 (s), 1267 (s), 1173 (s), 1098 (s), 1070(s), 1040 (m), 963 (m), 893 (m) cm⁻¹; ¹HNMR (500 MHz, CDCl₃) δ 9.76 (dd,J=3.0, 1.5 Hz, 1H), 7.59 (s, 1H), 6.63 (m, 1H), 6.31 (d, J=16.0 Hz, 1H),6.28 (s, 1H), 5.55 (s, 1H), 4.81 (s, 2H), 4.74 (dd, J=11.2, 4.5 Hz, 1H),4.43 (m, 5H), 4.24 (dd, J=11.2, 4.8 Hz, 1H), 3.98 (m, 1H), 3.93 (m, 2H),3.58 (d, J=10.1 Hz, 1H), 3.56 (m, 1H), 3.20 (s, 1H), 3.16 (s, 1H), 2.70(m, 1H), 2.56 (m, 1H), 2.48 (dd, J=16.0, 4.8 Hz, 1H), 2.40 (ddd, J=13.0,4.6, 4.5 Hz, 2H), 2.28 (m, 1H), 2.16 (ddd, J=14.1, 9.3, 5.6 Hz, 1H),2.09 (m, 1H), 2.04 (dd, J=13.4, 6.0 Hz, 2H), 1.91 (m, 1H), 1.83 (s, 3H),1.79 (m, 2H), 1.56 (m, 1H), 0.96 (d, J=7.1 Hz, 3H), 0.72 (d, J=6.7 Hz,3H); ¹³CNMR (125 MHz, CDCl₃) δ 200.5, 163.9, 161.0, 145.3, 140.5, 139.8,135.4, 135.3, 118.6, 111.4, 96.3, 87.1, 81.7, 80.5, 76.7, 74.0, 68.7,67.2, 66.9, 62.7, 62.4, 47.6, 39.4, 39.2, 38.8, 35.8, 35.3, 34.6, 33.5,32.0, 30.8, 29.6, 19.1, 12.9, 6.0; high resolution mass spectrum (ES⁺)m/z 928.1787 [(M+H); calcd for C₃₅H₄₅F₆INO₁₁PH: 928.1757].

Z-C(2-3) Macrocycle (+)-3.43Z:

18-Crown-6 (3.98 g, 15.1 mmol) and solid potassium carbonate (0.446 g,3.23 mmol) were added to a flask charged with freshly distilled toluene(195 mL) at room temperature under an argon atmosphere. After stirringfor three hours, a solution of phosphonate ester (+)-3.S₆ (0.25 g, 0.27mmol) in freshly distilled toluene (170 mL) was added dropwise viacannula and allowed to stir at room temperature. After two hours, thereaction mixture was poured into saturated aqueous sodium chloride (100mL) and the layers of the resultant biphasic mixture were separated. Theaqueous layer was extracted with EtOAc (30 mL, 4×), dried over MgSO₄,filtered and concentrated under reduced pressure. Purification viasilica gel chromatography afforded Z-C(2-3) macrocycle (+)-3.43Z (0.102g, 57% yield) and E-C(2-3) macrocycle (+)-3.43E (0.052 g, 29% yield)both as off white foams: Z-C(2-3) Macrocycle (+)-3.43Z: [α]_(D) ²⁰+25.7(c 0.2, CHCl₃); IR (neat) 2923 (s), 2843 (s), 1717 (s), 1653 (m), 1557(w), 1456 (w), 1280 (m), 1192 (m), 1149 (m), 1091 (s), 1018 (m), 886(w), 667 (s) cm⁻¹; ¹HNMR (500 MHz, C₆D₆) δ 7.61 (s, 1H), 6.92 (m, 1H),6.15 (d, J=15.9 Hz, 1H), 6.11 (s, 1H), 5.87 (dd, J=10.2, 2.0 Hz, 1H),5.55 (ddd, J=10.2, 10.1, 3.0 Hz, 1H), 5.45 (d, J=0.9 Hz, 1H), 5.26 (s,1H), 4.85 (s, 1H), 4.57 (dd, J=11.2, 4.4 Hz, 1H), 4.40 (m, 1H), 4.16(dd, J=11.8, 6.1 Hz, 1H), 4.01 (ddd, J=15.8, 11.3, 11.1 Hz, 1H), 3.91(dd, J=11.7, 4.4 Hz, 1H), 3.59 (app t, J=11.1 Hz, 1H), 3.46 (ddd,J=12.1, 11.7, 2.5 Hz, 1H), 3.34 (d, J=10.1 Hz, 1H), 3.34 (m, 1H), 2.91(d, J=12.2 Hz, 1H), 2.67 (app t, J=6.3 Hz, 1H), 2.51 (m, 2H), 2.36 (m,2H), 2.09 (m, 1H), 2.08 (d, J=12.7 Hz, 1H), 2.02 (d, J=11.2 Hz, 1H),1.94 (m, 1H), 1.88 (d, J=0.9 Hz, 3H), 1.55 (m, 2H), 1.02 (d, J=6.9 Hz,3H), 0.84 (d, J=13.4 Hz, 1H), 0.68 (d, J=6.5 Hz, 3H); ¹³CNMR (125 MHz,CDCl₃) δ 165.5, 161.1, 145.7, 144.4, 141.4, 139.6, 134.6, 134.1, 120.8,119.1, 110.1, 97.0, 87.6, 81.7, 79.1, 78.2, 76.7, 73.2, 68.2, 67.0,41.1, 39.0, 36.8, 34.1, 32.5, 31.8, 30.3, 29.6, 19.1, 13.0, 5.7; highresolution mass spectrum (ES⁺) m/z 688.1736 [(M+Na)⁺; calcd forC₃₁H₄₀INO₇Na: 688.1747].

E-C(2-3) Macrocycle (+)-3.43E: (0.075 g, 42% yield) [α]_(D) ²⁰+84.6 (c2.9, CHCl₃); IR (neat) 2926 (b), 2853 (b), 1720 (s), 1656 (s), 1153 (s),1097 (s), 1010 (b), 755 (s); ¹HNMR (500 MHz, C₆D₆) δ 7.32 (s, 1H), 6.68(m, 1H), 6.08 (d, J=16.0 Hz, 1H), 6.03 (d, J=15.4 Hz, 1H), 5.98 (s, 1H),5.34 (s, 1H), 4.97 (dd, J=11.1, 4.3 Hz, 1H), 4.72 (s, 1H); 4.66 (s, 1H),4.18 (m, 1H), 3.85 (dd, J=11.4, 3.8 Hz, 1H), 3.36 (m, 2H), 3.23 (m, 2H),3.17 (app t, J=9.9 Hz, 1H), 2.25 (m, 2H), 2.11 (m, 3H), 1.91 (dd,J=13.0, 3.1 Hz, 1H), 1.83 (m, 2H), 1.76 (s, 3H), 1.69 (m, 4H), 0.92 (appt, J=7.1 Hz, 1H), 0.88 (app t, J=7.0 Hz, 1H), 0.86 (d, J=6.7 Hz, 3H),0.75 (app t, J=7.1 Hz, 1H), 0.67 (d, J=6.5 Hz, 3H); ¹³CNMR (125 MHz,C₆H₆) δ 166.8, 161.9, 147.0, 146.6, 142.2, 141.1, 135.6, 123.8, 119.1,111.2, 95.6, 87.8, 81.2, 78.6, 77.4, 73.6, 70.5, 69.6, 66.6, 40.9, 40.7,38.6, 38.2, 34.7, 32.6, 31.9, 30.4, 19.4, 13.2, 6.2, 1.5; highresolution mass spectrum (ES⁺) m/z 688.0859 [(M+Na)⁺; calcd forC₃₁H₄₀INO₇Na: 688.0850].

C(33)-TES Acetal Side Chain (−)-3.56:

Oxazole 2.9 (0.74 g, 2.38 mmol) was added to a solution of dienyllactone (−)-2.80 Smith, et al. J. Am. Chem. Soc. 2001, 123, 10942)(0.255 g, 0.47 mmol) in freshly distilled tetrahydrofuran (THF) (22.4mL) at room temperature under an argon atmosphere. After cooling to 0°C., iso-propylmagnesium chloride (i-PrMgCl) (2.0 M/THF, 0.59 mL, 1.20mmol) was added dropwise over thirty minutes followed by stirring fortwenty minutes. Additional i-PrMgCl (2.0 M/THF, 0.59 mL, 1.20 mmol) wasadded dropwise over thirty minutes and allowed to stir for twentyminutes. A final addition of i-PrMgCl (2.0 M/THF, 0.59 mL, 1.20 mmol)was added dropwise over thirty minutes and after stirring for twentyminutes, the reaction was quenched via dropwise addition of saturatedaqueous sodium bicarbonate (10 mL). The layers of the biphasic solutionwere separated and the aqueous layer was extracted with EtOAc (10 mL,3×). The combined organic extracts were dried over MgSO₄, filtered, andconcentrated under reduced pressure. The resultant light orange oil wasfiltered through a plug of silica gel (30% EtOAc/hexanes) to afford thecorresponding hemi-acetal, which was immediately dissolved in freshlydistilled diethyl ether (1.4 mL) and anhydrous acetonitrile (1.0 mL).After cooling to −78° C. under an argon atmosphere, 2,6-lutidine (0.425mL, 3.66 mmol) was added followed by dropwise addition of triethylsilyltrifluoromethanesulfonate (TESOTf) (0.278 mL, 1.22 mmol). Aftertwenty-four hours, the reaction was quenched via dropwise addition ofsaturated aqueous sodium bicarbonate (3 mL) and allowed to warm to roomtemperature. The layers of the biphasic solution were separated and theaqueous layer was extracted with CH₂Cl₂ (5 mL, 3×). The combined organicextracts were dried over MgSO₄, filtered, and concentrated under reducedpressure. Purification via silica gel chromatography (5% EtOAc/hexanes)afforded C(33)-TES acetal side chain (−)-3.56 (0.224 g, 54% yield, 2steps) as a colorless oil: [α]_(D) ²⁰−8.4 (c 0.1, CHCl₃); IR (neat) 2958(b), 2868 (b), 2179 (s), 1591 (s), 1434 (s), 1231 (b), 1139 (s), 1094(s), 1000 (s), 853 (s), 606 (s); ¹HNMR (500 MHz, C₆D₆) δ 7.14 (s, 1H),6.25 (d, J=15.7 Hz, 1H), 5.73 (dd, J=15.7, 7.3 Hz, 1H), 5.53 (d, J=8.9Hz, 1H), 4.83 (dd, J=8.9, 4.9 Hz, 1H), 4.09 (m, 1H), 3.71 (m, 1H), 3.66(dd, J=9.9, 4.2 Hz, 1H), 3.27 (dd, J=13.9, 7.0 Hz, 1H), 3.15 (s, 3H),3.13 (s, 3H), 2.87 (d, J=14.2 Hz, 1H), 2.79 (d, J=14.3 Hz, 1H), 2.55(dd, J=16.8, 5.3 Hz, 1H), 2.43 (dd, J=16.7, 6.7 Hz, 1H), 2.37 (dd,J=10.3, 2.0 Hz, 1H), 2.26 (ddd, J=14.0, 4.1, 1.4 Hz, 1H), 1.83 (s, 3H),1.66 (app t, J=11.4 Hz, 1H), 1.12 (m, 21H), 1.00 (app t, J=7.9 Hz, 9H),0.65 (app q, J=7.9 Hz, 6H), 0.22 (s, 9H); ¹³CNMR (125 MHz, C₆D₆) δ159.0, 144.9, 137.1, 134.8, 132.6, 104.1, 99.3, 86.6, 80.6, 74.3, 73.9,70.9, 65.9, 56.4, 55.1, 42.3, 41.4, 31.4, 27.1, 18.3, 18.2, 15.5, 13.5,12.8, 7.2, 6.6, 0.22; high resolution mass spectrum (ES⁺) m/z 904.3924[(M+Na)⁺; calcd for C₄₀H₇₀F₃NO₉SSi₃Na: 904.3927].

C(33)-TES Stannyl Side Chain (−)-3.57:

C(33)-TES acetal side chain (−)-3.56 (0.028 g, 0.033 mmol) was combinedwith hexamethylditin [(Me₃Sn)₂] (0.015 g, 0.046 mmol) in a sealed tube(100 mL), azeotroped from benzene (2 mL, 3×), and dried under vacuum forthirty minutes. Flame dried lithium chloride (LiCl) (0.022 g, 0.52mmol), tetrakis(triphenylphosphine)palladium [Pd(PPh₃)₄] (5.6 mg, 0.005mmol) and anhydrous dioxane (0.50 mL, freeze pump thawed, 3×) were addedto the tube in a glove bag, under an argon atmosphere. The tube wassealed and heated to 90° C. with stirring behind a blast shield. Afterthirteen hours, the reaction mixture was cooled to room temperature andconcentrated under reduced pressure. The resultant dark brown slurry waspurified via silica gel chromatography (5% EtOAc/hexanes) to affordC(33)-TES stannyl side chain (−)-3.57 (0.016 g, 55% yield) as acolorless oil: [α]_(D) ²⁰−31.1 (c 0.1, CHCl₃); IR (neat) 2957 (b), 1462(s), 1248 (s), 1095 (b), 1000 (s), 843 (s), 743 (b); ¹HNMR (500 MHz,C₆D₆) δ 7.36 (s, 1H), 6.32 (d, J=15.7 Hz, 1H), 5.75 (dd, J=15.7, 7.3 Hz,1H), 5.64 (d, J=8.7 Hz, 1H), 4.90 (dd, J=8.6, 4.8 Hz, 1H), 4.18 (dd,J=11.9, 4.7 Hz, 1H), 3.79 (m, 1H), 3.69 (dd, J=13.1, 6.8 Hz, 1H), 3.28(d, J=14.4 Hz, 1H), 3.23 (d, J=14.3 Hz, 1H), 3.14 (s, 3H), 3.13 (s, 3H),2.58 (dd, J=16.7, 5.5 Hz, 1H), 2.51 (dd, J=12.5, 4.2 Hz, 1H), 2.44 (dd,J=16.7, 6.9 Hz, 1H), 2.39 (d, J=12.3 Hz, 1H), 1.90 (s, 3H), 1.76 (app t,J=12.2 Hz, 1H), 1.34 (m, 1H), 1.16 (m, 21H), 1.06 (app t, J=7.9 Hz, 9H),0.76 (app q, J=15.7 Hz, 6H), 0.27 (s, 9H), 0.23 (s, 9H); ¹³CNMR (125MHz, C₆D₆) δ 161.7, 145.6, 137.7, 135.1, 133.5, 104.6, 100.3, 86.9,81.1, 74.8, 74.5, 71.8, 56.8, 55.5, 42.8, 42.3, 32.2, 30.6, 27.8, 18.7,18.6, 14.1, 13.2, 7.7, 7.1, 0.6, −9.3; high resolution mass spectrum(ES⁺) m/z 920.4139 [(M+Na)⁺; calcd for C₄₂H₇₉NO₆Si₃SnNa: 920.4012].

Protected Z-C(2-3) Acetal Alkynyl Phorboxazole (+)-3.S₇Z:

Z-C(2-3) macrocycle (+)-3.43Z (3.9 mg, 0.006 mmol) was combined withC(33)-TES stannyl side chain (−)-3.57 (7.8 mg, 0.009 mmol) in aflame-dried round-bottom flask (5 mL), azeotroped from benzene (1 mL,3×) and dried under vacuum for two hours.Tris(dibenzylideneacetone)dipalladium-chloroform adduct[Pd₂(dba)₃.CHCl₃] (1.2 mg, 0.001 mmol), triphenylarsine (AsPh₃) (2.2 mg,0.007 mmol), and Ph₂PO₂NBu₄ (4.1 mg, 0.009 mmol) followed by DMF (0.1mL, sparged with argon for thirty minutes) and N,N-diisopropylethylamine(0.001 mL, 0.006 mmol) were added to the flask and the reaction stirredat room temperature under an argon atmosphere. After seventeen hours,the light brown reaction mixture was introduced directly onto a silicagel column (25% EtOAc/hexanes) to afford protected Z-C(2-3) acetalalkynyl phorboxazole (+)-3.S₇Z (5.2 mg, 68% yield) as a light yellowoil: [α]_(D) ²⁰+6.7 (c 0.3, CHCl₃); IR (neat) 2924 (b), 1720 (s), 1651(w), 1463 (s), 1376 (w), 1247 (w), 1091 (s), 1018 (b), 843 (s), 742 (w);¹HNMR (500 MHz, C₆D₆) δ 7.52 (s, 1H), 7.33 (s, 1H), 6.89 (m, 1H), 6.38(s, 1H), 6.31 (d, J=15.7 Hz, 1H), 6.09 (d, J=15.7 Hz, 1H), 5.81 (dd,J=11.4, 2.5 Hz, 1H), 5.74 (dd, J=15.7, 7.3 Hz, 1H), 5.63 (d, J=8.9 Hz,1H), 5.47 (ddd, J=10.2, 10.2, 3.1 Hz, 1H), 5.38 (s, 1H), 5.19 (s, 1H),4.90 (dd, J=8.5, 4.6 Hz, 1H), 4.79 (s, 1H), 4.62 (dd, J=11.2, 4.5 Hz,1H), 4.34 (br s, 1H), 4.28 (m, 1H), 4.08 (m, 1H), 3.95 (m, 1H), 3.82 (m,2H), 3.70 (dd, J=13.3, 6.8 Hz, 1H), 3.51 (app t, J=10.8 Hz, 1H), 3.45(d, J=10.0 Hz, 1H), 3.37 (m, 2H), 3.17 (d, J=2.5 Hz, 1H), 3.16 (s, 3H),3.13 (s, 3H), 2.83 (d, J=12.6 Hz, 1H), 2.67 (m, 1H), 2.59 (dd, J=16.7,5.7 Hz, 1H), 2.49 (m, 2H), 2.40 (m, 4H), 2.15 (s, 3H), 2.10 (m, 2H),2.03 (m, 3H), 1.95 (app t, J=11.8 Hz, 1H), 1.90 (s, 3H), 1.51 (m, 4H),1.15 (m, 21H), 1.06 (app t, J=7.9 Hz, 9H), 1.04 (d, J=6.9 Hz, 3H), 0.93(m, 1H), 0.79 (d, J=6.4 Hz, 3H), 0.75 (app q, J=8.1 Hz, 6H), 0.23 (s,9H); ¹³CNMR (125 MHz, C₆D₆) δ 165.4, 161.4, 159.8, 144.9, 142.5, 140.9,138.7, 137.7, 137.3, 136.6, 134.7, 134.3, 133.0, 121.1, 119.4, 119.1,110.2, 99.8, 97.5, 89.6, 86.5, 80.7, 80.0, 78.5, 74.4, 74.1, 73.4, 73.3,71.3, 68.9, 66.8, 56.4, 55.1, 42.4, 41.8, 41.4, 39.8, 37.5, 34.5, 32.8,31.8, 30.7, 30.2, 30.1, 27.5, 22.9, 18.4, 18.3, 14.2, 13.7, 13.4, 12.8,7.3, 7.0, 6.7, 6.1, 2.3; high resolution mass spectrum (ES⁺) m/z1293.7257 [(M+Na)⁺; calcd for C₇₀H₁₁₀N₂O₁₃Si₃Na: 1293.7212].

Protected E-C(2-3) Acetal Alkynyl Phorboxazole (+)-3.S₇E:

E-C(2-3) macrocycle (+)-3.43E (4.6 mg, 0.007 mmol) was combined withC(33)-TES stannyl side chain (−)-3.57 (9.2 mg, 0.010 mmol) in aflame-dried round-bottom flask (5 mL), azeotroped from benzene (1 mL,3×) and dried under vacuum for two hours.Tris(dibenzylideneacetone)dipalladium-chloroform adduct[Pd₂(dba)₃.CHCl₃] (1.4 mg, 0.001 mmol), triphenylarsine (AsPh₃) (2.5 mg,0.008 mmol), and Ph₂PO₂NBu₄ (4.7 mg, 0.01 mmol) followed by DMF (0.13mL, sparged with argon for thirty minutes) and N,N-diisopropylethylamine(0.002 mL, 0.01 mmol) were added to the flask and the reaction stirredat room temperature under an argon atmosphere. After twenty hours, thelight brown reaction mixture was introduced directly onto a silica gelcolumn (40% EtOAc/hexanes) to afford protected E-C(2-3) acetal alkynylphorboxazole (+)-3.S₇E (5.3 mg, 60% yield) as a light yellow oil.[α]_(D) ²⁰+2.7 (c 0.1, CHCl₃); IR (neat) 2929 (b), 2866 (b), 1717 (s),1652 (w), 1464 (s), 1247 (s), 1153 (s), 1099 (s), 1009 (b), 842 (s), 742(s); ¹HNMR (500 MHz, C₆D₆) δ 7.33 (s, 1H), 7.30 (s, 1H), 6.70 (m, 1H),6.33 (s, 1H), 6.30 (d, J=15.7 Hz, 1H), 6.11 (d, J=16.1 Hz, 1H), 6.05 (d,J=15.4 Hz, 1H), 5.73 (dd, J=15.7, 7.4 Hz, 1H), 5.63 (d, J=8.9 Hz, 1H),5.36 (s, 1H), 5.09 (dd, J=11.1, 4.2 Hz, 1H), 4.89 (dd, J=8.6, 4.7 Hz,1H), 4.72 (s, 1H), 4.66 (s, 1H), 4.16 (m, 2H), 3.86 (dd, J=11.6, 4.5 Hz,1H), 3.81 (m, 1H), 3.69 (dd, J=13.1, 6.7 Hz, 1H), 3.43 (d, J=9.9 Hz,1H), 3.37 (m, 3H), 3.18 (m, 1H), 3.15 (s, 3H), 3.12 (s, 3H), 2.58 (dd,J=16.7, 5.7 Hz, 1H), 2.48 (m, 2H), 2.39 (m, 2H), 2.25 (m, 3H), 2.16 (m,2H), 2.11 (s, 3H), 1.92 (dd, J=12.9, 3.1 Hz, 1H), 1.89 (s, 3H), 1.84(app t, J=12.3 Hz, 1H), 1.82 (m, 1H), 1.72 (m, 3H), 1.49 (m, 3H), 1.33(m, 4H), 1.17 (m, 21H), 1.05 (app t, J=7.9 Hz, 9H), 0.95 (d, J=6.7 Hz,3H), 0.86 (d, J=6.5 Hz, 3H), 0.75 (app q, J=7.8 Hz, 6H), 0.23 (s, 9H);¹³CNMR (125 MHz, C₆D₆) δ 183.0, 170.4, 166.7, 161.7, 159.7, 146.6,142.1, 140.9, 138.7, 137.8, 137.3, 136.5, 135.7, 135.4, 134.7, 132.9,131.8, 126.7, 123.7, 118.9, 118.8, 110.9, 104.4, 99.8, 95.5, 89.6, 86.5,80.7, 78.9, 77.1, 74.4, 74.1, 73.3, 71.4, 70.3, 66.4, 56.4, 55.1, 42.4,41.8, 40.9, 40.4, 38.5, 34.7, 34.6, 31.8, 30.2, 27.5, 18.4, 18.3, 14.2,13.7, 13.4, 12.8, 7.4, 6.7, 0.3; high resolution mass spectrum (ES⁺) m/z1293.7274 [(M+Na)⁺; calcd for C₇₀H₁₁₀N₂O₁₃Si₃Na: 1293.7212].

Z-C(2-3) C(11-15)-Acetal Alkynyl Phorboxazole (+)-3.42Z:

Protected Z-C(2-3) acetal alkynyl phorboxazole (+)-3.S₇Z (6.7 mg, 0.005mmol) was dissolved in freshly distilled tetrahydrofuran (THF) (1.3 mL)under argon at 0° C. After stirring for five minutes tetrabutylammoniumfluoride (TBAF) (1.0 M/THF, 0.021 mL, 0.02 mmol) was added dropwise viasyringe. After one hour, the reaction was quenched via dropwise additionof saturated aqueous sodium bicarbonate (1.5 mL) and warmed to roomtemperature. The layers of the biphasic mixture were separated and theaqueous layer was extracted with EtOAc (3 mL, 4×). The combined organicextracts were dried over MgSO₄, filtered and concentrated under reducedpressure. Purification via silica gel chromatography (100% EtOAc)afforded Z-C(2-3) C(11-15)-acetal alkynyl phorboxazole (+)-3.42Z (3.7mg, 80% yield) as an amorphous solid. [α]_(D) ²⁰+37.4 (c 0.1, CHCl₃); IR(neat) 3356 (b), 2940 (b), 2356 (w), 1712 (s), 1455 (s), 1365 (s), 1230(s), 1175 (s), 903 (s), 848 (s), 735 (s); ¹HNMR (500 MHz, C₆D₆) δ 7.53(s, 1H), 7.03 (s, 1H), 6.90 (m, 1H), 6.23 (d, J=15.9 Hz, 1H), 6.21 (s,1H), 6.11 (d, J=15.9 Hz, 1H), 5.82 (dd, J=11.5, 2.2 Hz, 1H), 5.59 (dd,J=15.7, 7.6 Hz, 1H), 5.56 (d, J=8.9 Hz, 1H), 5.45 (ddd, J=13.1, 10.1,3.0 Hz, 1H), 5.38 (d, J=0.7 Hz, 1H), 5.20 (s, 1H), 4.80 (s, 1H), 4.62(dd, J=11.2, 4.3 Hz, 1H), 4.35 (m, 2H), 4.08 (m, 1H), 3.96 (m, 2H), 3.83(dd, J=11.4, 4.5 Hz, 1H), 3.78 (m, 1H), 3.63 (dd, J=13.7, 6.6 Hz, 1H),3.51 (app t, J=11.2 Hz, 1H), 3.40 (app t, J=9.9 Hz, 1H), 3.39 (m, 1H),3.09 (s, 3H), 3.07 (s, 3H), 2.84 (d, J=15.2 Hz, 1H), 2.69 (d, J=15.1 Hz,1H), 2.68 (m, 1H), 2.46 (m, 1H), 2.40 (m, 5H), 2.31 (dd, J=6.6, 2.7 Hz,1H), 2.28 (dd, J=11.2, 3.0 Hz, 1H), 2.00 (m, 4H), 1.95 (s, 3H), 1.78(app t, J=2.7 Hz, 1H), 1.65 (d, J=0.9 Hz, 3H), 1.51 (m, 3H), 1.31 (m,4H), 1.05 (d, J=6.9 Hz, 3H), 0.9 (m, 2H), 0.7 (d, J=6.4 Hz, 3H); ¹³CNMR(125 MHz, C₆D₆) δ 161.0, 145.3, 142.7, 141.1, 138.9, 137.7, 137.1,136.1, 134.9, 134.3, 131.8, 129.8, 121.2, 119.7, 118.5, 110.1, 97.7,97.1, 89.5, 80.9, 80.1, 78.7, 73.6, 73.5, 73.1, 71.2, 70.5, 69.1, 67.0,56.5, 55.5, 41.6, 41.3, 41.2, 40.0, 37.7, 35.8, 34.7, 33.7, 33.0, 32.3,32.2, 30.9, 30.4, 30.3, 30.1, 29.9, 26.4, 25.8, 14.5, 13.5, 6.3; highresolution mass spectrum (ES⁺) m/z 951.4637 [(M+Na)⁺; calcd forC₅₂H₆₈N₂O₁₃Na: 951.4618].

E-C(2-3) C(11-15)-Acetal Alkynyl Phorboxazole (+)-3.42E:

Protected E-C(2-3) acetal alkynyl phorboxazole (+)-3.S₇E (0.010 g, 0.008mmol) was dissolved in freshly distilled tetrahydrofuran (THF) (1.9 mL)under argon at 0° C. After stirring for five minutes, tetrabutylammoniumfluoride (TBAF) (1.0 M/THF, 0.031 mL, 0.03 mmol) was added dropwise viasyringe. After one hour, the reaction was quenched via dropwise additionof saturated aqueous sodium bicarbonate (2.0 mL) and allowed to warm toroom temperature. The layers of the biphasic mixture were separated andthe aqueous layer was extracted with EtOAc (3 mL, 4×), dried over MgSO₄,filtered and concentrated under reduced pressure. Purification viasilica gel chromatography (100% EtOAc) afforded E-C(2-3) C(11-15)-acetalalkynyl phorboxazole (+)-3.42E (6.0 mg, 81% yield) as an amorphoussolid. [α]_(D) ²⁰+21.8 (c 0.1, CH₂Cl₂), IR (neat) 3305 (b), 2926 (b),2853 (s), 1714 (s), 1655 (s), 1456 (b), 1362 (b), 1153 (s), 1097 (s),1010 (b), 879 (w); ¹HNMR (500 MHz, C₆D₆) δ 7.40 (s, 1H), 7.31 (s, 1H),6.83 (m, 1H), 6.31 (d, J=15.8 Hz, 1H), 6.26 (s, 1H), 6.22 (d, J=16.1 Hz,1H), 6.16 (d, J=15.4 Hz, 1H), 5.67 (dd, J=15.6, 7.5 Hz, 1H), 5.64 (d,J=8.8 Hz, 1H), 5.52 (s, 1H), 5.45 (s, 1H), 5.19 (dd, J=10.1, 4.1 Hz,1H), 4.82 (s, 1H), 4.75 (s, 1H), 4.43 (app t, J=7.3 Hz, 1H), 4.29 (m,1H), 4.05 (dd, J=10.2, 4.5 Hz, 1H), 3.95 (dd, J=11.7, 4.5 Hz, 1H), 3.87(m, 1H), 3.72 (dd, J=14.1, 7.3 Hz, 1H), 3.47 (m, 3H), 3.28 (app t,J=10.2 Hz, 1H), 3.18 (s, 3H), 3.16 (s, 3H), 2.92 (d, J=15.4 Hz, 1H),2.78 (d, J=15.4 Hz, 1H), 2.55 (dd, J=5.8, 2.7 Hz, 1H), 2.52 (dd, J=5.8,2.6 Hz, 1H), 2.50 (m, 1H), 2.44 (dd, J=6.6, 2.7 Hz, 1H), 2.40 (dd,J=6.7, 2.8 Hz, 1H), 2.34 (m, 4H), 2.18 (m, 2H), 2.11 (m, 1H), 2.04 (m,2H), 1.99 (s, 3H), 1.92 (m, 1H), 1.87 (app t, J=2.6 Hz, 1H), 1.81 (m,3H), 1.74 (s, 3H), 1.61 (m, 2H), 1.36 (m, 3H), 1.07 (d, J=6.7 Hz, 3H),1.01 (m, 2H), 0.92 (d, J=6.5 Hz, 1H); ¹³CNMR (125 MHz, C₆D₆) δ 167.3,162.4, 161.3, 147.3, 142.6, 141.5, 139.4, 138.7, 138.1, 137.4, 136.4,136.3, 135.9, 132.2, 124.3, 119.5, 118.8, 111.5, 97.4, 96.1, 89.9, 81.5,81.2, 79.4, 77.8, 73.9, 73.4, 71.6, 70.9, 66.9, 56.8, 55.9, 41.7, 41.4,41.1, 40.4, 39.0, 38.6, 35.2, 35.1, 34.1, 33.1, 32.3, 30.7, 30.6, 30.6,26.8, 23.6, 14.9, 14.0, 13.9, 6.7; high resolution mass spectrum (ES⁺)m/z 951.4636 [(M+Na)⁺; calcd for C₅₂H₆₈N₂O₁₃Na: 951.4669].

Biological Data (Analogues Will be Referred to in Roman Numerals inDiscussing Biological Data)

With (+)-phorboxazole A (XVIII) and the eight phorboxazole analogues inhand, biological evaluation against a diverse panel of human cancer celllines was conducted in the laboratory of Professor George R. Pettit atthe Cancer Research Institute of Arizona State University. Specifically,cancer growth inhibition efficacy was evaluated against the human cancercell lines; BXP-3 (pancreatic), MCF-3 (breast), F-268 (CNS), NCI-H460(non-small lung), KM20L2 (colon), and DU-145 (prostate) (Smith, et al.Org. Lett. 2005, 7, 4403; Smith, et al. Org. Lett. 2005, 8, 797). As aresult of the biological testing, several analogues were found to be asactive and in several cell lines, significantly more active thanphorboxazole A. In addition to the potent congeners, several inactiveanalogues were identified, providing direct evidence of importantfunctionality required for potent tumor cell growth inhibitory activity.

Evaluation of (+)-phorboxazole A (XVIII) against the human cancer cellline panel revealed an average growth inhibition (GI₅₀) of 5.0 nanomolar(nM), a value within experimental error of previously reported results(Table 1). Screening the previously disclosed (+)-Z-C(2-3)-C(45-46)alkynyl phorboxazole congener (XVIIaZ) (Uckun, et al. Bioorg. Med. Chem.Lett. 2001, 11, 1181) against the six cancer cell lines afforded anaverage GI₅₀ of 5.2 nM, comparable to the Forsyth analogue studies.While structurally more rigid than the C(45-46) vinyl bromide, thealkyne substitution does not appear to adversely affect the binding ofthe phorboxazole skeleton with cellular targets. Conversely,(+)-E-C(2-3)-C(45-46)-alkynyl phorboxazole analogue (XVIIaE) was foundto be significantly less active than (XVIII) and (XVIIaZ). An averageGI₅₀ of 281 nM was found, implicating the importance of theconformational geometry imparted by Z-C(2-3) macrocyclic enoate forpotent activity.

Evaluation of C(45-46) alkenyl (XVIIc) and alkyl (XVIIb) analoguesagainst the human cancer cell line panel revealed average GI₅₀ data of4.1 and 3.1 nM respectively, values slightly more potent than(+)-phorboxazole A (ca. 5.0 nM). Specifically, alkyl congener (XVIIb)displayed single digit GI₅₀ values of 1.6 and 1.3 nM against thenon-small lung and colon cancer cell lines. Not only does the greaterflexibility of the C(45-46) alkenyl and alkyl congeners seem not toaffect activity but, the decreased electronic density of thesesubstitutions also does not seem to play a significant role in theirbiological properties. When vinyl chloride analogue (XVIId) was screenedagainst the six human cancer cell lines however, extraordinarysub-nanomolar efficacy of 0.62, 0.49, 0.64, and 0.38 nM was observedagainst the pancreatic, CNS, non-small lung, and colon cancer celllines, respectively. Though both sterically and conformationally verysimilar to (+)-phorboxazole A, the greater activity of (XVIId) may beaccounted for by the small difference in electron deficiency between thevinyl chloride and bromide, possibly promoting a more favorable bindingwith the cell machinery responsible for the observed cytotoxicity.

As mentioned previously, the synthetically simplified C(11-15) acetalcongeners (XVIIfZ) and (XVIIfE) were thought to impart a similarconformational geometry as the tetrahydropyran however, the importanceof the C(13) hydroxyl was unknown. When screened against the six cancercell lines, Z-C(2-3) acetal conger (XVIIfZ) revealed an average GI₅₀value of 34.6 nM, and in particular 18.3 and 11.8 nM were observed forthe breast and colon cancer cell lines, respectively. The E-acetalisomer (XVIIfE), however was found to be significantly less active. Anaverage GI₅₀ of 943.5 nM was observed, reinforcing the importance of theZ-C(2-3) enoate conformational for potent activity. While the Z-acetalisomer was slightly less active than the corresponding C(11-15)tetrahydropyran series, a similar conformation does appear to be presentrelative to the tetrahydropyran based upon proton NMR. In addition,interactions with cellular targets by the C(13) hydroxyl does not appearto play a significant role toward the cytotoxicity of the phorboxazoles.In accord with the Forsyth data, the truncated central tetrahydropyrananalogue (XVIIe) was found to be inactive across the entire cell linepanel. This reinforces the need for an elaborate macrocyclic domain,possibly to impart a specific conformational geometry to the side chainrelative to the macrocycle.

TABLE 1 Biological evaluation of phorboxazole analogues.

In summary, the C(45-46), C(2-3), and C(11-15) phorboxazole analogueshave shed considerable light on the conformational and functional grouprequirements for potent tumor cell growth inhibitory activity.Specifically, C(45-46) alkynyl (XVIIaZ), alkenyl (XVIIc), and alkyl(XVIIb) congers displayed activity comparable to that of(+)-phorboxazole A. Vinyl chloride (XVIId) proved to be an extremelypotent sub-nanomolar congener with activity greater than that of(+)-phorboxazole A. The macrocyclic C(2-3) geometrical conformationappears to play an extremely important role toward biological activity.For example, the Z isomer displayed activity two-orders of magnitudegreater than that of the E-isomer in both the C(11-15) acetal andtetrahydropyran series. Finally, by mimicking the C(11-15)tetrahydropyran, acetal congener (XVIIfZ) proved to be both asynthetically and structurally simplified potent agent.

When ranges are used herein, such as carbon ranges or dosage ranges, allcombinations and subcombinations of ranges and specific embodimentstherein are intended to be included.

The disclosures of each patent, patent application and publication citedor described in this document are hereby incorporated herein byreference, in their entirety.

Those skilled in the art will appreciate that numerous changes andmodifications can be made to the preferred embodiments of the inventionand that such changes and modifications can be made without departingfrom the spirit of the invention. It is, therefore, intended that theappended claims cover all such equivalent variations as fall within thetrue spirit and scope of the invention.

1-5. (canceled)
 6. A process for preparing a compound of formula XX:

wherein: each R² is independently H, alkyl, aralkyl, aryl, or anhydroxyl protecting group; and each Z is H or taken together form anexocyclic methylene moiety, comprising the steps of: contacting acompound of formula:

with a compound of formula:

 a lactonization agent, and a base for a time and under conditionseffective to provide a compound of formula XX. 7-8. (canceled)
 9. Amethod of inducing apoptosis in malignant cells, comprising the step of:contacting said cells with an effective amount of a compound of formulaXIX:

wherein: R¹ is alkyl, alkenyl, haloalkenyl, or alkynyl; each R² isindependently H, alkyl, aralkyl, aryl, or an hydroxyl protecting group;each dotted line indicates independently the presence of a single ordouble bond; and each Z is H or taken together form an exocyclicmethylene moiety provided that when the compound of formula XIX has thestructure:

 and R² is H or methyl: then R¹ is other than:


10. A method according to claim 9, wherein said apoptosis occurs invitro.
 11. A method according to claim 9, wherein said apoptosis occursin vivo.
 12. A method for inhibiting cancer cell division, comprisingthe step of: contacting said cells with an effective amount of acompound of formula XIX:

wherein: R¹ is alkyl, alkenyl, haloalkenyl, or alkynyl; each R² isindependently H, alkyl, aralkyl, aryl, or an hydroxyl protecting group;each dotted line indicates independently the presence of a single ordouble bond; and each Z is H or taken together form an exocyclicmethylene moiety; provided that when the compound of formula XIX has thestructure:

 and R² is H or methyl; then R¹ is other than:


13. (canceled)
 14. A method for treating cancer in a patient in needthereof, comprising the step of: administering to said patient aneffective amount of a compound of formula XIX:

wherein: R¹ is alkyl alkenyl haloalkenyl or alkynyl: each R² isindependently H, alkyl, aralkyl, aryl, or an hydroxyl protecting group;each dotted line indicates independently the presence of a single ordouble bond; and each Z is H or taken together form an exocyclicmethylene moiety; provided that when the compound of formula XIX has thestructure:

 and R² is H or methyl: then R¹ is other than:

 wherein the cancer treated is selected from the group consisting ofpancreatic, breast, central nervous system, non-small lung, colon, andprostate cancers. 15-23. (canceled)
 24. A process for preparing acompound of formula XXIII:

wherein: each R² is independently H, alkyl, aralkyl, aryl, or anhydroxyl protecting group; and each Z is H or taken together form anexocyclic methylene moiety, comprising the steps of: contacting acompound of formula:

with a compound of formula:

 a lactonization agent, and a base for a time and under conditionseffective to provide a compound of formula XXIII. 25-27. (canceled) 28.A method of inducing apoptosis in malignant cells, comprising the stepof: contacting said cells with an effective amount of a compound offormula XXII:

wherein: G is —O— or —CH₂—: Q is H or OR², provided that when G is —O—then Q is H; R¹ is alkyl, alkenyl, haloalkenyl, or alkynyl; each R² isindependently H, alkyl, aralkyl, aryl, or an hydroxyl protecting group;each dotted line indicates independently the presence of a single ordouble bond; and each Z is H or taken together form an exocyclicmethylene moiety; provided that when the compound of formula XXII hasthe structure:

 and R² is H or methyl; then R¹ is other than:

wherein said apoptosis occurs in vitro.
 29. A method of inducingapoptosis in malignant cells, comprising the step of: contacting saidcells with an effective amount of a compound of formula XXII:

wherein: G is —O— or —CH₂—: Q is H or OR provided that when G is —O—then Q is H; R¹ is alkyl alkenyl haloalkenyl or alkynyl; each R² isindependently H, alkyl aralkyl aryl or an hydroxyl protecting group;each dotted line indicates independently the presence of a single ordouble bond; and each Z is H or taken together form an exocyclicmethylene moiety; provided that when the compound of formula XXII hasthe structure:

 and R² is H or methyl; then R¹ is other than:

wherein said apoptosis occurs in vivo.
 30. A method for inhibitingcancer cell division, comprising the step of: contacting said cells withan effective amount of a compound of formula XXII:

wherein: G is —O— or —CH₂—; Q is H or OR², provided that when G is —O—,then Q is H; R¹ is alkyl alkenyl haloalkenyl or alkynyl: each R² isindependently H, alkyl aralkyl aryl or an hydroxyl protecting group;each dotted line indicates independently the presence of a single ordouble bond; and each Z is H or taken together form an exocyclicmethylene moiety: provided that when the compound of formula XXII hasthe structure:

 and R² is H or methyl; then R¹ is other than:


31. (canceled)
 32. A method for treating cancer in a patient in needthereof comprising the step of: administering to said patient aneffective amount of a compound of formula

wherein: G is —O— or —CH₂—; Q is H or OR², provided that when G is —O—then Q is H; R¹ is alkyl alkenyl haloalkenyl or alkynyl; each R² isindependently H, alkyl aralkyl aryl or an hydroxyl protecting group;each dotted line indicates independently the presence of a single ordouble bond; and each Z is H or taken together form an exocyclicmethylene moiety provided that when the compound of formula XXII has thestructure:

 and R² is H or methyl; then R¹ is other than:

 wherein the cancer treated is selected from the group consisting ofpancreatic, breast, central nervous system, non-small lung, colon, andprostate cancers.